/* * Copyright (C)2009-2015, 2017, 2020-2023 D. R. Commander. * All Rights Reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * - Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * - Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * - Neither the name of the libjpeg-turbo Project nor the names of its * contributors may be used to endorse or promote products derived from this * software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS", * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #ifndef __TURBOJPEG_H__ #define __TURBOJPEG_H__ #include #if defined(_WIN32) && defined(DLLDEFINE) #define DLLEXPORT __declspec(dllexport) #else #define DLLEXPORT #endif #define DLLCALL /** * @addtogroup TurboJPEG * TurboJPEG API. This API provides an interface for generating, decoding, and * transforming planar YUV and JPEG images in memory. * * @anchor YUVnotes * YUV Image Format Notes * ---------------------- * Technically, the JPEG format uses the YCbCr colorspace (which is technically * not a colorspace but a color transform), but per the convention of the * digital video community, the TurboJPEG API uses "YUV" to refer to an image * format consisting of Y, Cb, and Cr image planes. * * Each plane is simply a 2D array of bytes, each byte representing the value * of one of the components (Y, Cb, or Cr) at a particular location in the * image. The width and height of each plane are determined by the image * width, height, and level of chrominance subsampling. The luminance plane * width is the image width padded to the nearest multiple of the horizontal * subsampling factor (1 in the case of 4:4:4, grayscale, 4:4:0, or 4:4:1; 2 in * the case of 4:2:2 or 4:2:0; 4 in the case of 4:1:1.) Similarly, the * luminance plane height is the image height padded to the nearest multiple of * the vertical subsampling factor (1 in the case of 4:4:4, 4:2:2, grayscale, * or 4:1:1; 2 in the case of 4:2:0 or 4:4:0; 4 in the case of 4:4:1.) This is * irrespective of any additional padding that may be specified as an argument * to the various YUV functions. The chrominance plane width is equal to the * luminance plane width divided by the horizontal subsampling factor, and the * chrominance plane height is equal to the luminance plane height divided by * the vertical subsampling factor. * * For example, if the source image is 35 x 35 pixels and 4:2:2 subsampling is * used, then the luminance plane would be 36 x 35 bytes, and each of the * chrominance planes would be 18 x 35 bytes. If you specify a row alignment * of 4 bytes on top of this, then the luminance plane would be 36 x 35 bytes, * and each of the chrominance planes would be 20 x 35 bytes. * * @{ */ /** * The number of initialization options */ #define TJ_NUMINIT 3 /** * Initialization options. */ enum TJINIT { /** * Initialize the TurboJPEG instance for compression. */ TJINIT_COMPRESS, /** * Initialize the TurboJPEG instance for decompression. */ TJINIT_DECOMPRESS, /** * Initialize the TurboJPEG instance for lossless transformation (both * compression and decompression.) */ TJINIT_TRANSFORM }; /** * The number of chrominance subsampling options */ #define TJ_NUMSAMP 7 /** * Chrominance subsampling options. * When pixels are converted from RGB to YCbCr (see #TJCS_YCbCr) or from CMYK * to YCCK (see #TJCS_YCCK) as part of the JPEG compression process, some of * the Cb and Cr (chrominance) components can be discarded or averaged together * to produce a smaller image with little perceptible loss of image clarity. * (The human eye is more sensitive to small changes in brightness than to * small changes in color.) This is called "chrominance subsampling". */ enum TJSAMP { /** * 4:4:4 chrominance subsampling (no chrominance subsampling). The JPEG or * YUV image will contain one chrominance component for every pixel in the * source image. */ TJSAMP_444, /** * 4:2:2 chrominance subsampling. The JPEG or YUV image will contain one * chrominance component for every 2x1 block of pixels in the source image. */ TJSAMP_422, /** * 4:2:0 chrominance subsampling. The JPEG or YUV image will contain one * chrominance component for every 2x2 block of pixels in the source image. */ TJSAMP_420, /** * Grayscale. The JPEG or YUV image will contain no chrominance components. */ TJSAMP_GRAY, /** * 4:4:0 chrominance subsampling. The JPEG or YUV image will contain one * chrominance component for every 1x2 block of pixels in the source image. * * @note 4:4:0 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_440, /** * 4:1:1 chrominance subsampling. The JPEG or YUV image will contain one * chrominance component for every 4x1 block of pixels in the source image. * JPEG images compressed with 4:1:1 subsampling will be almost exactly the * same size as those compressed with 4:2:0 subsampling, and in the * aggregate, both subsampling methods produce approximately the same * perceptual quality. However, 4:1:1 is better able to reproduce sharp * horizontal features. * * @note 4:1:1 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_411, /** * 4:4:1 chrominance subsampling. The JPEG or YUV image will contain one * chrominance component for every 1x4 block of pixels in the source image. * JPEG images compressed with 4:4:1 subsampling will be almost exactly the * same size as those compressed with 4:2:0 subsampling, and in the * aggregate, both subsampling methods produce approximately the same * perceptual quality. However, 4:4:1 is better able to reproduce sharp * vertical features. * * @note 4:4:1 subsampling is not fully accelerated in libjpeg-turbo. */ TJSAMP_441, /** * Unknown subsampling. The JPEG image uses an unusual type of chrominance * subsampling. Such images can be decompressed into packed-pixel images, * but they cannot be * - decompressed into planar YUV images, * - losslessly transformed if #TJXOPT_CROP is specified, or * - partially decompressed using a cropping region. */ TJSAMP_UNKNOWN = -1 }; /** * MCU block width (in pixels) for a given level of chrominance subsampling. * MCU block sizes: * - 8x8 for no subsampling or grayscale * - 16x8 for 4:2:2 * - 8x16 for 4:4:0 * - 16x16 for 4:2:0 * - 32x8 for 4:1:1 * - 8x32 for 4:4:1 */ static const int tjMCUWidth[TJ_NUMSAMP] = { 8, 16, 16, 8, 8, 32, 8 }; /** * MCU block height (in pixels) for a given level of chrominance subsampling. * MCU block sizes: * - 8x8 for no subsampling or grayscale * - 16x8 for 4:2:2 * - 8x16 for 4:4:0 * - 16x16 for 4:2:0 * - 32x8 for 4:1:1 * - 8x32 for 4:4:1 */ static const int tjMCUHeight[TJ_NUMSAMP] = { 8, 8, 16, 8, 16, 8, 32 }; /** * The number of pixel formats */ #define TJ_NUMPF 12 /** * Pixel formats */ enum TJPF { /** * RGB pixel format. The red, green, and blue components in the image are * stored in 3-sample pixels in the order R, G, B from lowest to highest * memory address within each pixel. */ TJPF_RGB, /** * BGR pixel format. The red, green, and blue components in the image are * stored in 3-sample pixels in the order B, G, R from lowest to highest * memory address within each pixel. */ TJPF_BGR, /** * RGBX pixel format. The red, green, and blue components in the image are * stored in 4-sample pixels in the order R, G, B from lowest to highest * memory address within each pixel. The X component is ignored when * compressing and undefined when decompressing. */ TJPF_RGBX, /** * BGRX pixel format. The red, green, and blue components in the image are * stored in 4-sample pixels in the order B, G, R from lowest to highest * memory address within each pixel. The X component is ignored when * compressing and undefined when decompressing. */ TJPF_BGRX, /** * XBGR pixel format. The red, green, and blue components in the image are * stored in 4-sample pixels in the order R, G, B from highest to lowest * memory address within each pixel. The X component is ignored when * compressing and undefined when decompressing. */ TJPF_XBGR, /** * XRGB pixel format. The red, green, and blue components in the image are * stored in 4-sample pixels in the order B, G, R from highest to lowest * memory address within each pixel. The X component is ignored when * compressing and undefined when decompressing. */ TJPF_XRGB, /** * Grayscale pixel format. Each 1-sample pixel represents a luminance * (brightness) level from 0 to the maximum sample value (255 for 8-bit * samples, 4095 for 12-bit samples, and 65535 for 16-bit samples.) */ TJPF_GRAY, /** * RGBA pixel format. This is the same as @ref TJPF_RGBX, except that when * decompressing, the X component is guaranteed to be equal to the maximum * sample value, which can be interpreted as an opaque alpha channel. */ TJPF_RGBA, /** * BGRA pixel format. This is the same as @ref TJPF_BGRX, except that when * decompressing, the X component is guaranteed to be equal to the maximum * sample value, which can be interpreted as an opaque alpha channel. */ TJPF_BGRA, /** * ABGR pixel format. This is the same as @ref TJPF_XBGR, except that when * decompressing, the X component is guaranteed to be equal to the maximum * sample value, which can be interpreted as an opaque alpha channel. */ TJPF_ABGR, /** * ARGB pixel format. This is the same as @ref TJPF_XRGB, except that when * decompressing, the X component is guaranteed to be equal to the maximum * sample value, which can be interpreted as an opaque alpha channel. */ TJPF_ARGB, /** * CMYK pixel format. Unlike RGB, which is an additive color model used * primarily for display, CMYK (Cyan/Magenta/Yellow/Key) is a subtractive * color model used primarily for printing. In the CMYK color model, the * value of each color component typically corresponds to an amount of cyan, * magenta, yellow, or black ink that is applied to a white background. In * order to convert between CMYK and RGB, it is necessary to use a color * management system (CMS.) A CMS will attempt to map colors within the * printer's gamut to perceptually similar colors in the display's gamut and * vice versa, but the mapping is typically not 1:1 or reversible, nor can it * be defined with a simple formula. Thus, such a conversion is out of scope * for a codec library. However, the TurboJPEG API allows for compressing * packed-pixel CMYK images into YCCK JPEG images (see #TJCS_YCCK) and * decompressing YCCK JPEG images into packed-pixel CMYK images. */ TJPF_CMYK, /** * Unknown pixel format. Currently this is only used by #tj3LoadImage8(), * #tj3LoadImage12(), and #tj3LoadImage16(). */ TJPF_UNKNOWN = -1 }; /** * Red offset (in samples) for a given pixel format. This specifies the number * of samples that the red component is offset from the start of the pixel. * For instance, if an 8-bit-per-component pixel of format TJPF_BGRX is stored * in `unsigned char pixel[]`, then the red component will be * `pixel[tjRedOffset[TJPF_BGRX]]`. This will be -1 if the pixel format does * not have a red component. */ static const int tjRedOffset[TJ_NUMPF] = { 0, 2, 0, 2, 3, 1, -1, 0, 2, 3, 1, -1 }; /** * Green offset (in samples) for a given pixel format. This specifies the * number of samples that the green component is offset from the start of the * pixel. For instance, if an 8-bit-per-component pixel of format TJPF_BGRX is * stored in `unsigned char pixel[]`, then the green component will be * `pixel[tjGreenOffset[TJPF_BGRX]]`. This will be -1 if the pixel format does * not have a green component. */ static const int tjGreenOffset[TJ_NUMPF] = { 1, 1, 1, 1, 2, 2, -1, 1, 1, 2, 2, -1 }; /** * Blue offset (in samples) for a given pixel format. This specifies the * number of samples that the blue component is offset from the start of the * pixel. For instance, if an 8-bit-per-component pixel of format TJPF_BGRX is * stored in `unsigned char pixel[]`, then the blue component will be * `pixel[tjBlueOffset[TJPF_BGRX]]`. This will be -1 if the pixel format does * not have a blue component. */ static const int tjBlueOffset[TJ_NUMPF] = { 2, 0, 2, 0, 1, 3, -1, 2, 0, 1, 3, -1 }; /** * Alpha offset (in samples) for a given pixel format. This specifies the * number of samples that the alpha component is offset from the start of the * pixel. For instance, if an 8-bit-per-component pixel of format TJPF_BGRA is * stored in `unsigned char pixel[]`, then the alpha component will be * `pixel[tjAlphaOffset[TJPF_BGRA]]`. This will be -1 if the pixel format does * not have an alpha component. */ static const int tjAlphaOffset[TJ_NUMPF] = { -1, -1, -1, -1, -1, -1, -1, 3, 3, 0, 0, -1 }; /** * Pixel size (in samples) for a given pixel format */ static const int tjPixelSize[TJ_NUMPF] = { 3, 3, 4, 4, 4, 4, 1, 4, 4, 4, 4, 4 }; /** * The number of JPEG colorspaces */ #define TJ_NUMCS 5 /** * JPEG colorspaces */ enum TJCS { /** * RGB colorspace. When compressing the JPEG image, the R, G, and B * components in the source image are reordered into image planes, but no * colorspace conversion or subsampling is performed. RGB JPEG images can be * compressed from and decompressed to packed-pixel images with any of the * extended RGB or grayscale pixel formats, but they cannot be compressed * from or decompressed to planar YUV images. */ TJCS_RGB, /** * YCbCr colorspace. YCbCr is not an absolute colorspace but rather a * mathematical transformation of RGB designed solely for storage and * transmission. YCbCr images must be converted to RGB before they can * actually be displayed. In the YCbCr colorspace, the Y (luminance) * component represents the black & white portion of the original image, and * the Cb and Cr (chrominance) components represent the color portion of the * original image. Originally, the analog equivalent of this transformation * allowed the same signal to drive both black & white and color televisions, * but JPEG images use YCbCr primarily because it allows the color data to be * optionally subsampled for the purposes of reducing network or disk usage. * YCbCr is the most common JPEG colorspace, and YCbCr JPEG images can be * compressed from and decompressed to packed-pixel images with any of the * extended RGB or grayscale pixel formats. YCbCr JPEG images can also be * compressed from and decompressed to planar YUV images. */ TJCS_YCbCr, /** * Grayscale colorspace. The JPEG image retains only the luminance data (Y * component), and any color data from the source image is discarded. * Grayscale JPEG images can be compressed from and decompressed to * packed-pixel images with any of the extended RGB or grayscale pixel * formats, or they can be compressed from and decompressed to planar YUV * images. */ TJCS_GRAY, /** * CMYK colorspace. When compressing the JPEG image, the C, M, Y, and K * components in the source image are reordered into image planes, but no * colorspace conversion or subsampling is performed. CMYK JPEG images can * only be compressed from and decompressed to packed-pixel images with the * CMYK pixel format. */ TJCS_CMYK, /** * YCCK colorspace. YCCK (AKA "YCbCrK") is not an absolute colorspace but * rather a mathematical transformation of CMYK designed solely for storage * and transmission. It is to CMYK as YCbCr is to RGB. CMYK pixels can be * reversibly transformed into YCCK, and as with YCbCr, the chrominance * components in the YCCK pixels can be subsampled without incurring major * perceptual loss. YCCK JPEG images can only be compressed from and * decompressed to packed-pixel images with the CMYK pixel format. */ TJCS_YCCK }; /** * Parameters */ enum TJPARAM { /** * Error handling behavior * * **Value** * - `0` *[default]* Allow the current compression/decompression/transform * operation to complete unless a fatal error is encountered. * - `1` Immediately discontinue the current * compression/decompression/transform operation if a warning (non-fatal * error) occurs. */ TJPARAM_STOPONWARNING, /** * Row order in packed-pixel source/destination images * * **Value** * - `0` *[default]* top-down (X11) order * - `1` bottom-up (Windows, OpenGL) order */ TJPARAM_BOTTOMUP, /** * JPEG destination buffer (re)allocation [compression, lossless * transformation] * * **Value** * - `0` *[default]* Attempt to allocate or reallocate the JPEG destination * buffer as needed. * - `1` Generate an error if the JPEG destination buffer is invalid or too * small. */ TJPARAM_NOREALLOC, /** * Perceptual quality of lossy JPEG images [compression only] * * **Value** * - `1`-`100` (`1` = worst quality but best compression, `100` = best * quality but worst compression) *[no default; must be explicitly * specified]* */ TJPARAM_QUALITY, /** * Chrominance subsampling level * * The JPEG or YUV image uses (decompression, decoding) or will use (lossy * compression, encoding) the specified level of chrominance subsampling. * * **Value** * - One of the @ref TJSAMP "chrominance subsampling options" *[no default; * must be explicitly specified for lossy compression, encoding, and * decoding]* */ TJPARAM_SUBSAMP, /** * JPEG width (in pixels) [decompression only, read-only] */ TJPARAM_JPEGWIDTH, /** * JPEG height (in pixels) [decompression only, read-only] */ TJPARAM_JPEGHEIGHT, /** * JPEG data precision (bits per sample) [decompression only, read-only] * * The JPEG image uses the specified number of bits per sample. * * **Value** * - `8`, `12`, or `16` * * 12-bit data precision implies #TJPARAM_OPTIMIZE unless #TJPARAM_ARITHMETIC * is set. */ TJPARAM_PRECISION, /** * JPEG colorspace * * The JPEG image uses (decompression) or will use (lossy compression) the * specified colorspace. * * **Value** * - One of the @ref TJCS "JPEG colorspaces" *[default for lossy compression: * automatically selected based on the subsampling level and pixel format]* */ TJPARAM_COLORSPACE, /** * Chrominance upsampling algorithm [lossy decompression only] * * **Value** * - `0` *[default]* Use smooth upsampling when decompressing a JPEG image * that was compressed using chrominance subsampling. This creates a smooth * transition between neighboring chrominance components in order to reduce * upsampling artifacts in the decompressed image. * - `1` Use the fastest chrominance upsampling algorithm available, which * may combine upsampling with color conversion. */ TJPARAM_FASTUPSAMPLE, /** * DCT/IDCT algorithm [lossy compression and decompression] * * **Value** * - `0` *[default]* Use the most accurate DCT/IDCT algorithm available. * - `1` Use the fastest DCT/IDCT algorithm available. * * This parameter is provided mainly for backward compatibility with libjpeg, * which historically implemented several different DCT/IDCT algorithms * because of performance limitations with 1990s CPUs. In the libjpeg-turbo * implementation of the TurboJPEG API: * - The "fast" and "accurate" DCT/IDCT algorithms perform similarly on * modern x86/x86-64 CPUs that support AVX2 instructions. * - The "fast" algorithm is generally only about 5-15% faster than the * "accurate" algorithm on other types of CPUs. * - The difference in accuracy between the "fast" and "accurate" algorithms * is the most pronounced at JPEG quality levels above 90 and tends to be * more pronounced with decompression than with compression. * - The "fast" algorithm degrades and is not fully accelerated for JPEG * quality levels above 97, so it will be slower than the "accurate" * algorithm. */ TJPARAM_FASTDCT, /** * Optimized baseline entropy coding [lossy compression only] * * **Value** * - `0` *[default]* The JPEG image will use the default Huffman tables. * - `1` Optimal Huffman tables will be computed for the JPEG image. For * lossless transformation, this can also be specified using * #TJXOPT_OPTIMIZE. * * Optimized baseline entropy coding will improve compression slightly * (generally 5% or less), but it will reduce compression performance * considerably. */ TJPARAM_OPTIMIZE, /** * Progressive entropy coding * * **Value** * - `0` *[default for compression, lossless transformation]* The lossy JPEG * image uses (decompression) or will use (compression, lossless * transformation) baseline entropy coding. * - `1` The lossy JPEG image uses (decompression) or will use (compression, * lossless transformation) progressive entropy coding. For lossless * transformation, this can also be specified using #TJXOPT_PROGRESSIVE. * * Progressive entropy coding will generally improve compression relative to * baseline entropy coding, but it will reduce compression and decompression * performance considerably. Can be combined with #TJPARAM_ARITHMETIC. * Implies #TJPARAM_OPTIMIZE unless #TJPARAM_ARITHMETIC is also set. */ TJPARAM_PROGRESSIVE, /** * Progressive JPEG scan limit for lossy JPEG images [decompression, lossless * transformation] * * Setting this parameter will cause the decompression and transform * functions to return an error if the number of scans in a progressive JPEG * image exceeds the specified limit. The primary purpose of this is to * allow security-critical applications to guard against an exploit of the * progressive JPEG format described in * this report. * * **Value** * - maximum number of progressive JPEG scans that the decompression and * transform functions will process *[default: `0` (no limit)]* * * @see #TJPARAM_PROGRESSIVE */ TJPARAM_SCANLIMIT, /** * Arithmetic entropy coding * * **Value** * - `0` *[default for compression, lossless transformation]* The lossy JPEG * image uses (decompression) or will use (compression, lossless * transformation) Huffman entropy coding. * - `1` The lossy JPEG image uses (decompression) or will use (compression, * lossless transformation) arithmetic entropy coding. For lossless * transformation, this can also be specified using #TJXOPT_ARITHMETIC. * * Arithmetic entropy coding will generally improve compression relative to * Huffman entropy coding, but it will reduce compression and decompression * performance considerably. Can be combined with #TJPARAM_PROGRESSIVE. */ TJPARAM_ARITHMETIC, /** * Lossless JPEG * * **Value** * - `0` *[default for compression]* The JPEG image is (decompression) or * will be (compression) lossy/DCT-based. * - `1` The JPEG image is (decompression) or will be (compression) * lossless/predictive. * * In most cases, compressing and decompressing lossless JPEG images is * considerably slower than compressing and decompressing lossy JPEG images, * and lossless JPEG images are much larger than lossy JPEG images. Thus, * lossless JPEG images are typically used only for applications that require * mathematically lossless compression. Also note that the following * features are not available with lossless JPEG images: * - Colorspace conversion (lossless JPEG images always use #TJCS_RGB, * #TJCS_GRAY, or #TJCS_CMYK, depending on the pixel format of the source * image) * - Chrominance subsampling (lossless JPEG images always use #TJSAMP_444) * - JPEG quality selection * - DCT/IDCT algorithm selection * - Progressive entropy coding * - Arithmetic entropy coding * - Compression from/decompression to planar YUV images * - Decompression scaling * - Lossless transformation * * @see #TJPARAM_LOSSLESSPSV, #TJPARAM_LOSSLESSPT */ TJPARAM_LOSSLESS, /** * Lossless JPEG predictor selection value (PSV) * * **Value** * - `1`-`7` *[default for compression: `1`]* * * Lossless JPEG compression shares no algorithms with lossy JPEG * compression. Instead, it uses differential pulse-code modulation (DPCM), * an algorithm whereby each sample is encoded as the difference between the * sample's value and a "predictor", which is based on the values of * neighboring samples. If Ra is the sample immediately to the left of the * current sample, Rb is the sample immediately above the current sample, and * Rc is the sample diagonally to the left and above the current sample, then * the relationship between the predictor selection value and the predictor * is as follows: * * PSV | Predictor * ----|---------- * 1 | Ra * 2 | Rb * 3 | Rc * 4 | Ra + Rb – Rc * 5 | Ra + (Rb – Rc) / 2 * 6 | Rb + (Ra – Rc) / 2 * 7 | (Ra + Rb) / 2 * * Predictors 1-3 are 1-dimensional predictors, whereas Predictors 4-7 are * 2-dimensional predictors. The best predictor for a particular image * depends on the image. * * @see #TJPARAM_LOSSLESS */ TJPARAM_LOSSLESSPSV, /** * Lossless JPEG point transform (Pt) * * **Value** * - `0` through ***precision*** *- 1*, where ***precision*** is the JPEG * data precision in bits *[default for compression: `0`]* * * A point transform value of `0` is necessary in order to generate a fully * lossless JPEG image. (A non-zero point transform value right-shifts the * input samples by the specified number of bits, which is effectively a form * of lossy color quantization.) * * @see #TJPARAM_LOSSLESS, #TJPARAM_PRECISION */ TJPARAM_LOSSLESSPT, /** * JPEG restart marker interval in MCU blocks (lossy) or samples (lossless) * [compression only] * * The nature of entropy coding is such that a corrupt JPEG image cannot * be decompressed beyond the point of corruption unless it contains restart * markers. A restart marker stops and restarts the entropy coding algorithm * so that, if a JPEG image is corrupted, decompression can resume at the * next marker. Thus, adding more restart markers improves the fault * tolerance of the JPEG image, but adding too many restart markers can * adversely affect the compression ratio and performance. * * **Value** * - the number of MCU blocks or samples between each restart marker * *[default: `0` (no restart markers)]* * * Setting this parameter to a non-zero value sets #TJPARAM_RESTARTROWS to 0. */ TJPARAM_RESTARTBLOCKS, /** * JPEG restart marker interval in MCU rows (lossy) or sample rows (lossless) * [compression only] * * See #TJPARAM_RESTARTBLOCKS for a description of restart markers. * * **Value** * - the number of MCU rows or sample rows between each restart marker * *[default: `0` (no restart markers)]* * * Setting this parameter to a non-zero value sets #TJPARAM_RESTARTBLOCKS to * 0. */ TJPARAM_RESTARTROWS, /** * JPEG horizontal pixel density * * **Value** * - The JPEG image has (decompression) or will have (compression) the * specified horizontal pixel density *[default for compression: `1`]*. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value of #TJPARAM_DENSITYUNITS * is `2`. * * @see TJPARAM_DENSITYUNITS */ TJPARAM_XDENSITY, /** * JPEG vertical pixel density * * **Value** * - The JPEG image has (decompression) or will have (compression) the * specified vertical pixel density *[default for compression: `1`]*. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value of #TJPARAM_DENSITYUNITS * is `2`. * * @see TJPARAM_DENSITYUNITS */ TJPARAM_YDENSITY, /** * JPEG pixel density units * * **Value** * - `0` *[default for compression]* The pixel density of the JPEG image is * expressed (decompression) or will be expressed (compression) in unknown * units. * - `1` The pixel density of the JPEG image is expressed (decompression) or * will be expressed (compression) in units of pixels/inch. * - `2` The pixel density of the JPEG image is expressed (decompression) or * will be expressed (compression) in units of pixels/cm. * * This value is stored in or read from the JPEG header. It does not affect * the contents of the JPEG image. Note that this parameter is set by * #tj3LoadImage8() when loading a Windows BMP file that contains pixel * density information, and the value of this parameter is stored to a * Windows BMP file by #tj3SaveImage8() if the value is `2`. * * @see TJPARAM_XDENSITY, TJPARAM_YDENSITY */ TJPARAM_DENSITYUNITS, /** * Memory limit for intermediate buffers * * **Value** * - the maximum amount of memory (in megabytes) that will be allocated for * intermediate buffers, which are used with progressive JPEG compression and * decompression, optimized baseline entropy coding, lossless JPEG * compression, and lossless transformation *[default: `0` (no limit)]* */ TJPARAM_MAXMEMORY, /** * Image size limit [decompression, lossless transformation, packed-pixel * image loading] * * Setting this parameter will cause the decompression, transform, and image * loading functions to return an error if the number of pixels in the source * image exceeds the specified limit. This allows security-critical * applications to guard against excessive memory consumption. * * **Value** * - maximum number of pixels that the decompression, transform, and image * loading functions will process *[default: `0` (no limit)]* */ TJPARAM_MAXPIXELS }; /** * The number of error codes */ #define TJ_NUMERR 2 /** * Error codes */ enum TJERR { /** * The error was non-fatal and recoverable, but the destination image may * still be corrupt. */ TJERR_WARNING, /** * The error was fatal and non-recoverable. */ TJERR_FATAL }; /** * The number of transform operations */ #define TJ_NUMXOP 8 /** * Transform operations for #tj3Transform() */ enum TJXOP { /** * Do not transform the position of the image pixels */ TJXOP_NONE, /** * Flip (mirror) image horizontally. This transform is imperfect if there * are any partial MCU blocks on the right edge (see #TJXOPT_PERFECT.) */ TJXOP_HFLIP, /** * Flip (mirror) image vertically. This transform is imperfect if there are * any partial MCU blocks on the bottom edge (see #TJXOPT_PERFECT.) */ TJXOP_VFLIP, /** * Transpose image (flip/mirror along upper left to lower right axis.) This * transform is always perfect. */ TJXOP_TRANSPOSE, /** * Transverse transpose image (flip/mirror along upper right to lower left * axis.) This transform is imperfect if there are any partial MCU blocks in * the image (see #TJXOPT_PERFECT.) */ TJXOP_TRANSVERSE, /** * Rotate image clockwise by 90 degrees. This transform is imperfect if * there are any partial MCU blocks on the bottom edge (see * #TJXOPT_PERFECT.) */ TJXOP_ROT90, /** * Rotate image 180 degrees. This transform is imperfect if there are any * partial MCU blocks in the image (see #TJXOPT_PERFECT.) */ TJXOP_ROT180, /** * Rotate image counter-clockwise by 90 degrees. This transform is imperfect * if there are any partial MCU blocks on the right edge (see * #TJXOPT_PERFECT.) */ TJXOP_ROT270 }; /** * This option will cause #tj3Transform() to return an error if the transform * is not perfect. Lossless transforms operate on MCU blocks, whose size * depends on the level of chrominance subsampling used (see #tjMCUWidth and * #tjMCUHeight.) If the image's width or height is not evenly divisible by * the MCU block size, then there will be partial MCU blocks on the right * and/or bottom edges. It is not possible to move these partial MCU blocks to * the top or left of the image, so any transform that would require that is * "imperfect." If this option is not specified, then any partial MCU blocks * that cannot be transformed will be left in place, which will create * odd-looking strips on the right or bottom edge of the image. */ #define TJXOPT_PERFECT (1 << 0) /** * This option will cause #tj3Transform() to discard any partial MCU blocks * that cannot be transformed. */ #define TJXOPT_TRIM (1 << 1) /** * This option will enable lossless cropping. See #tj3Transform() for more * information. */ #define TJXOPT_CROP (1 << 2) /** * This option will discard the color data in the source image and produce a * grayscale destination image. */ #define TJXOPT_GRAY (1 << 3) /** * This option will prevent #tj3Transform() from outputting a JPEG image for * this particular transform. (This can be used in conjunction with a custom * filter to capture the transformed DCT coefficients without transcoding * them.) */ #define TJXOPT_NOOUTPUT (1 << 4) /** * This option will enable progressive entropy coding in the JPEG image * generated by this particular transform. Progressive entropy coding will * generally improve compression relative to baseline entropy coding (the * default), but it will reduce decompression performance considerably. * Can be combined with #TJXOPT_ARITHMETIC. Implies #TJXOPT_OPTIMIZE unless * #TJXOPT_ARITHMETIC is also specified. */ #define TJXOPT_PROGRESSIVE (1 << 5) /** * This option will prevent #tj3Transform() from copying any extra markers * (including EXIF and ICC profile data) from the source image to the * destination image. */ #define TJXOPT_COPYNONE (1 << 6) /** * This option will enable arithmetic entropy coding in the JPEG image * generated by this particular transform. Arithmetic entropy coding will * generally improve compression relative to Huffman entropy coding (the * default), but it will reduce decompression performance considerably. Can be * combined with #TJXOPT_PROGRESSIVE. */ #define TJXOPT_ARITHMETIC (1 << 7) /** * This option will enable optimized baseline entropy coding in the JPEG image * generated by this particular transform. Optimized baseline entropy coding * will improve compression slightly (generally 5% or less.) */ #define TJXOPT_OPTIMIZE (1 << 8) /** * Scaling factor */ typedef struct { /** * Numerator */ int num; /** * Denominator */ int denom; } tjscalingfactor; /** * Cropping region */ typedef struct { /** * The left boundary of the cropping region. This must be evenly divisible * by the MCU block width (see #tjMCUWidth.) */ int x; /** * The upper boundary of the cropping region. For lossless transformation, * this must be evenly divisible by the MCU block height (see #tjMCUHeight.) */ int y; /** * The width of the cropping region. Setting this to 0 is the equivalent of * setting it to the width of the source JPEG image - x. */ int w; /** * The height of the cropping region. Setting this to 0 is the equivalent of * setting it to the height of the source JPEG image - y. */ int h; } tjregion; /** * A #tjregion structure that specifies no cropping */ static const tjregion TJUNCROPPED = { 0, 0, 0, 0 }; /** * Lossless transform */ typedef struct tjtransform { /** * Cropping region */ tjregion r; /** * One of the @ref TJXOP "transform operations" */ int op; /** * The bitwise OR of one of more of the @ref TJXOPT_ARITHMETIC * "transform options" */ int options; /** * Arbitrary data that can be accessed within the body of the callback * function */ void *data; /** * A callback function that can be used to modify the DCT coefficients after * they are losslessly transformed but before they are transcoded to a new * JPEG image. This allows for custom filters or other transformations to be * applied in the frequency domain. * * @param coeffs pointer to an array of transformed DCT coefficients. (NOTE: * this pointer is not guaranteed to be valid once the callback returns, so * applications wishing to hand off the DCT coefficients to another function * or library should make a copy of them within the body of the callback.) * * @param arrayRegion #tjregion structure containing the width and height of * the array pointed to by `coeffs` as well as its offset relative to the * component plane. TurboJPEG implementations may choose to split each * component plane into multiple DCT coefficient arrays and call the callback * function once for each array. * * @param planeRegion #tjregion structure containing the width and height of * the component plane to which `coeffs` belongs * * @param componentID ID number of the component plane to which `coeffs` * belongs. (Y, Cb, and Cr have, respectively, ID's of 0, 1, and 2 in * typical JPEG images.) * * @param transformID ID number of the transformed image to which `coeffs` * belongs. This is the same as the index of the transform in the * `transforms` array that was passed to #tj3Transform(). * * @param transform a pointer to a #tjtransform structure that specifies the * parameters and/or cropping region for this transform * * @return 0 if the callback was successful, or -1 if an error occurred. */ int (*customFilter) (short *coeffs, tjregion arrayRegion, tjregion planeRegion, int componentID, int transformID, struct tjtransform *transform); } tjtransform; /** * TurboJPEG instance handle */ typedef void *tjhandle; /** * Compute the scaled value of `dimension` using the given scaling factor. * This macro performs the integer equivalent of `ceil(dimension * * scalingFactor)`. */ #define TJSCALED(dimension, scalingFactor) \ (((dimension) * scalingFactor.num + scalingFactor.denom - 1) / \ scalingFactor.denom) /** * A #tjscalingfactor structure that specifies a scaling factor of 1/1 (no * scaling) */ static const tjscalingfactor TJUNSCALED = { 1, 1 }; #ifdef __cplusplus extern "C" { #endif /** * Create a new TurboJPEG instance. * * @param initType one of the @ref TJINIT "initialization options" * * @return a handle to the newly-created instance, or NULL if an error occurred * (see #tj3GetErrorStr().) */ DLLEXPORT tjhandle tj3Init(int initType); /** * Set the value of a parameter. * * @param handle handle to a TurboJPEG instance * * @param param one of the @ref TJPARAM "parameters" * * @param value value of the parameter (refer to @ref TJPARAM * "parameter documentation") * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3Set(tjhandle handle, int param, int value); /** * Get the value of a parameter. * * @param handle handle to a TurboJPEG instance * * @param param one of the @ref TJPARAM "parameters" * * @return the value of the specified parameter, or -1 if the value is unknown. */ DLLEXPORT int tj3Get(tjhandle handle, int param); /** * Compress an 8-bit-per-sample packed-pixel RGB, grayscale, or CMYK image into * an 8-bit-per-sample JPEG image. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK source image to be compressed. This buffer should normally be * `pitch * height` samples in size. However, you can also use this parameter * to compress from a specific region of a larger buffer. * * @param width width (in pixels) of the source image * * @param pitch samples per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to compress from a specific region of a larger buffer. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize(). This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * If you choose option 1, then `*jpegSize` should be set to the size of your * pre-allocated buffer. In any case, unless you have set #TJPARAM_NOREALLOC, * you should always check `*jpegBuf` upon return from this function, as it may * have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Upon return, `*jpegSize` will * contain the size of the JPEG image (in bytes.) If `*jpegBuf` points to a * JPEG buffer that is being reused from a previous call to one of the JPEG * compression functions, then `*jpegSize` is ignored. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Compress8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a 12-bit-per-sample packed-pixel RGB, grayscale, or CMYK image into * a 12-bit-per-sample JPEG image. * * \details \copydetails tj3Compress8() */ DLLEXPORT int tj3Compress12(tjhandle handle, const short *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a 16-bit-per-sample packed-pixel RGB, grayscale, or CMYK image into * a 16-bit-per-sample lossless JPEG image. * * \details \copydetails tj3Compress8() */ DLLEXPORT int tj3Compress16(tjhandle handle, const unsigned short *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress an 8-bit-per-sample unified planar YUV image into an * 8-bit-per-sample JPEG image. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a unified planar YUV source * image to be compressed. The size of this buffer should match the value * returned by #tj3YUVBufSize() for the given image width, height, row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes should be stored sequentially in the * buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param width width (in pixels) of the source image. If the width is not an * even multiple of the MCU block width (see #tjMCUWidth), then an intermediate * buffer copy will be performed. * * @param align row alignment (in bytes) of the source image (must be a power * of 2.) Setting this parameter to n indicates that each row in each plane of * the source image is padded to the nearest multiple of n bytes * (1 = unpadded.) * * @param height height (in pixels) of the source image. If the height is not * an even multiple of the MCU block height (see #tjMCUHeight), then an * intermediate buffer copy will be performed. * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize(). This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * If you choose option 1, then `*jpegSize` should be set to the size of your * pre-allocated buffer. In any case, unless you have set #TJPARAM_NOREALLOC, * you should always check `*jpegBuf` upon return from this function, as it may * have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Upon return, `*jpegSize` will * contain the size of the JPEG image (in bytes.) If `*jpegBuf` points to a * JPEG buffer that is being reused from a previous call to one of the JPEG * compression functions, then `*jpegSize` is ignored. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3CompressFromYUV8(tjhandle handle, const unsigned char *srcBuf, int width, int align, int height, unsigned char **jpegBuf, size_t *jpegSize); /** * Compress a set of 8-bit-per-sample Y, U (Cb), and V (Cr) image planes into * an 8-bit-per-sample JPEG image. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if compressing a grayscale image) that contain a YUV * source image to be compressed. These planes can be contiguous or * non-contiguous in memory. The size of each plane should match the value * returned by #tj3YUVPlaneSize() for the given image width, height, strides, * and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) Refer to * @ref YUVnotes "YUV Image Format Notes" for more details. * * @param width width (in pixels) of the source image. If the width is not an * even multiple of the MCU block width (see #tjMCUWidth), then an intermediate * buffer copy will be performed. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV source image. Setting the stride * for any plane to 0 is the same as setting it to the plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective plane widths. You * can adjust the strides in order to specify an arbitrary amount of row * padding in each plane or to create a JPEG image from a subregion of a larger * planar YUV image. * * @param height height (in pixels) of the source image. If the height is not * an even multiple of the MCU block height (see #tjMCUHeight), then an * intermediate buffer copy will be performed. * * @param jpegBuf address of a pointer to a byte buffer that will receive the * JPEG image. TurboJPEG has the ability to reallocate the JPEG buffer to * accommodate the size of the JPEG image. Thus, you can choose to: * -# pre-allocate the JPEG buffer with an arbitrary size using #tj3Alloc() and * let TurboJPEG grow the buffer as needed, * -# set `*jpegBuf` to NULL to tell TurboJPEG to allocate the buffer for you, * or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize(). This should ensure that the buffer never has to be * re-allocated. (Setting #TJPARAM_NOREALLOC guarantees that it won't be.) * . * If you choose option 1, then `*jpegSize` should be set to the size of your * pre-allocated buffer. In any case, unless you have set #TJPARAM_NOREALLOC, * you should always check `*jpegBuf` upon return from this function, as it may * have changed. * * @param jpegSize pointer to a size_t variable that holds the size of the JPEG * buffer. If `*jpegBuf` points to a pre-allocated buffer, then `*jpegSize` * should be set to the size of the buffer. Upon return, `*jpegSize` will * contain the size of the JPEG image (in bytes.) If `*jpegBuf` points to a * JPEG buffer that is being reused from a previous call to one of the JPEG * compression functions, then `*jpegSize` is ignored. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3CompressFromYUVPlanes8(tjhandle handle, const unsigned char * const *srcPlanes, int width, const int *strides, int height, unsigned char **jpegBuf, size_t *jpegSize); /** * The maximum size of the buffer (in bytes) required to hold a JPEG image with * the given parameters. The number of bytes returned by this function is * larger than the size of the uncompressed source image. The reason for this * is that the JPEG format uses 16-bit coefficients, so it is possible for a * very high-quality source image with very high-frequency content to expand * rather than compress when converted to the JPEG format. Such images * represent very rare corner cases, but since there is no way to predict the * size of a JPEG image prior to compression, the corner cases have to be * handled. * * @param width width (in pixels) of the image * * @param height height (in pixels) of the image * * @param jpegSubsamp the level of chrominance subsampling to be used when * generating the JPEG image (see @ref TJSAMP * "Chrominance subsampling options".) #TJSAMP_UNKNOWN is treated like * #TJSAMP_444, since a buffer large enough to hold a JPEG image with no * subsampling should also be large enough to hold a JPEG image with an * arbitrary level of subsampling. Note that lossless JPEG images always * use #TJSAMP_444. * * @return the maximum size of the buffer (in bytes) required to hold the * image, or 0 if the arguments are out of bounds. */ DLLEXPORT size_t tj3JPEGBufSize(int width, int height, int jpegSubsamp); /** * The size of the buffer (in bytes) required to hold a unified planar YUV * image with the given parameters. * * @param width width (in pixels) of the image * * @param align row alignment (in bytes) of the image (must be a power of 2.) * Setting this parameter to n specifies that each row in each plane of the * image will be padded to the nearest multiple of n bytes (1 = unpadded.) * * @param height height (in pixels) of the image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the size of the buffer (in bytes) required to hold the image, or 0 * if the arguments are out of bounds. */ DLLEXPORT size_t tj3YUVBufSize(int width, int align, int height, int subsamp); /** * The size of the buffer (in bytes) required to hold a YUV image plane with * the given parameters. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param width width (in pixels) of the YUV image. NOTE: this is the width of * the whole image, not the plane width. * * @param stride bytes per row in the image plane. Setting this to 0 is the * equivalent of setting it to the plane width. * * @param height height (in pixels) of the YUV image. NOTE: this is the height * of the whole image, not the plane height. * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the size of the buffer (in bytes) required to hold the YUV image * plane, or 0 if the arguments are out of bounds. */ DLLEXPORT size_t tj3YUVPlaneSize(int componentID, int width, int stride, int height, int subsamp); /** * The plane width of a YUV image plane with the given parameters. Refer to * @ref YUVnotes "YUV Image Format Notes" for a description of plane width. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param width width (in pixels) of the YUV image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the plane width of a YUV image plane with the given parameters, or 0 * if the arguments are out of bounds. */ DLLEXPORT int tj3YUVPlaneWidth(int componentID, int width, int subsamp); /** * The plane height of a YUV image plane with the given parameters. Refer to * @ref YUVnotes "YUV Image Format Notes" for a description of plane height. * * @param componentID ID number of the image plane (0 = Y, 1 = U/Cb, 2 = V/Cr) * * @param height height (in pixels) of the YUV image * * @param subsamp level of chrominance subsampling in the image (see * @ref TJSAMP "Chrominance subsampling options".) * * @return the plane height of a YUV image plane with the given parameters, or * 0 if the arguments are out of bounds. */ DLLEXPORT int tj3YUVPlaneHeight(int componentID, int height, int subsamp); /** * Encode an 8-bit-per-sample packed-pixel RGB or grayscale image into an * 8-bit-per-sample unified planar YUV image. This function performs color * conversion (which is accelerated in the libjpeg-turbo implementation) but * does not execute any of the other steps in the JPEG compression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB or grayscale * source image to be encoded. This buffer should normally be `pitch * height` * bytes in size. However, you can also use this parameter to encode from a * specific region of a larger buffer. * * @param width width (in pixels) of the source image * * @param pitch bytes per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to encode from a specific region of a larger packed-pixel image. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param dstBuf pointer to a buffer that will receive the unified planar YUV * image. Use #tj3YUVBufSize() to determine the appropriate size for this * buffer based on the image width, height, row alignment, and level of * chrominance subsampling (see #TJPARAM_SUBSAMP.) The Y, U (Cb), and V (Cr) * image planes will be stored sequentially in the buffer. (Refer to * @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV image (must be a power of * 2.) Setting this parameter to n will cause each row in each plane of the * YUV image to be padded to the nearest multiple of n bytes (1 = unpadded.) * To generate images suitable for X Video, `align` should be set to 4. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3EncodeYUV8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int align); /** * Encode an 8-bit-per-sample packed-pixel RGB or grayscale image into separate * 8-bit-per-sample Y, U (Cb), and V (Cr) image planes. This function performs * color conversion (which is accelerated in the libjpeg-turbo implementation) * but does not execute any of the other steps in the JPEG compression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * compression * * @param srcBuf pointer to a buffer containing a packed-pixel RGB or grayscale * source image to be encoded. This buffer should normally be `pitch * height` * bytes in size. However, you can also use this parameter to encode from a * specific region of a larger buffer. * * * @param width width (in pixels) of the source image * * @param pitch bytes per row in the source image. Normally this should be * width * #tjPixelSize[pixelFormat], if the image is unpadded. * (Setting this parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat].) However, you can also use this * parameter to specify the row alignment/padding of the source image, to skip * rows, or to encode from a specific region of a larger packed-pixel image. * * @param height height (in pixels) of the source image * * @param pixelFormat pixel format of the source image (see @ref TJPF * "Pixel formats".) * * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if generating a grayscale image) that will receive the * encoded image. These planes can be contiguous or non-contiguous in memory. * Use #tj3YUVPlaneSize() to determine the appropriate size for each plane * based on the image width, height, strides, and level of chrominance * subsampling (see #TJPARAM_SUBSAMP.) Refer to @ref YUVnotes * "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV image. Setting the stride for any * plane to 0 is the same as setting it to the plane width (see @ref YUVnotes * "YUV Image Format Notes".) If `strides` is NULL, then the strides for all * planes will be set to their respective plane widths. You can adjust the * strides in order to add an arbitrary amount of row padding to each plane or * to encode an RGB or grayscale image into a subregion of a larger planar YUV * image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3EncodeYUVPlanes8(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **dstPlanes, int *strides); /** * Retrieve information about a JPEG image without decompressing it, or prime * the decompressor with quantization and Huffman tables. If a JPEG image is * passed to this function, then the @ref TJPARAM "parameters" that describe * the JPEG image will be set when the function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing a JPEG image or an * "abbreviated table specification" (AKA "tables-only") datastream. Passing a * tables-only datastream to this function primes the decompressor with * quantization and Huffman tables that can be used when decompressing * subsequent "abbreviated image" datastreams. This is useful, for instance, * when decompressing video streams in which all frames share the same * quantization and Huffman tables. * * @param jpegSize size of the JPEG image or tables-only datastream (in bytes) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressHeader(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize); /** * Returns a list of fractional scaling factors that the JPEG decompressor * supports. * * @param numScalingFactors pointer to an integer variable that will receive * the number of elements in the list * * @return a pointer to a list of fractional scaling factors, or NULL if an * error is encountered (see #tj3GetErrorStr().) */ DLLEXPORT tjscalingfactor *tj3GetScalingFactors(int *numScalingFactors); /** * Set the scaling factor for subsequent lossy decompression operations. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param scalingFactor #tjscalingfactor structure that specifies a fractional * scaling factor that the decompressor supports (see #tj3GetScalingFactors()), * or #TJUNSCALED for no scaling. Decompression scaling is a function * of the IDCT algorithm, so scaling factors are generally limited to multiples * of 1/8. If the entire JPEG image will be decompressed, then the width and * height of the scaled destination image can be determined by calling * #TJSCALED() with the JPEG width and height (see #TJPARAM_JPEGWIDTH and * #TJPARAM_JPEGHEIGHT) and the specified scaling factor. When decompressing * into a planar YUV image, an intermediate buffer copy will be performed if * the width or height of the scaled destination image is not an even multiple * of the MCU block size (see #tjMCUWidth and #tjMCUHeight.) Note that * decompression scaling is not available (and the specified scaling factor is * ignored) when decompressing lossless JPEG images (see #TJPARAM_LOSSLESS), * since the IDCT algorithm is not used with those images. Note also that * #TJPARAM_FASTDCT is ignored when decompression scaling is enabled. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SetScalingFactor(tjhandle handle, tjscalingfactor scalingFactor); /** * Set the cropping region for partially decompressing a lossy JPEG image into * a packed-pixel image * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param croppingRegion #tjregion structure that specifies a subregion of the * JPEG image to decompress, or #TJUNCROPPED for no cropping. The * left boundary of the cropping region must be evenly divisible by the scaled * MCU block width (#TJSCALED(#tjMCUWidth[subsamp], scalingFactor), * where `subsamp` is the level of chrominance subsampling in the JPEG image * (see #TJPARAM_SUBSAMP) and `scalingFactor` is the decompression scaling * factor (see #tj3SetScalingFactor().) The cropping region should be * specified relative to the scaled image dimensions. Unless `croppingRegion` * is #TJUNCROPPED, the JPEG header must be read (see * #tj3DecompressHeader()) prior to calling this function. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SetCroppingRegion(tjhandle handle, tjregion croppingRegion); /** * Decompress an 8-bit-per-sample JPEG image into an 8-bit-per-sample * packed-pixel RGB, grayscale, or CMYK image. The @ref TJPARAM "parameters" * that describe the JPEG image will be set when this function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstBuf pointer to a buffer that will receive the packed-pixel * decompressed image. This buffer should normally be * `pitch * destinationHeight` samples in size. However, you can also use this * parameter to decompress into a specific region of a larger buffer. NOTE: * If the JPEG image is lossy, then `destinationHeight` is either the scaled * JPEG height (see #TJSCALED(), #TJPARAM_JPEGHEIGHT, and * #tj3SetScalingFactor()) or the height of the cropping region (see * #tj3SetCroppingRegion().) If the JPEG image is lossless, then * `destinationHeight` is the JPEG height. * * @param pitch samples per row in the destination image. Normally this should * be set to destinationWidth * #tjPixelSize[pixelFormat], if the * destination image should be unpadded. (Setting this parameter to 0 is the * equivalent of setting it to * destinationWidth * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decompress into a specific region of * a larger buffer. NOTE: If the JPEG image is lossy, then `destinationWidth` * is either the scaled JPEG width (see #TJSCALED(), #TJPARAM_JPEGWIDTH, and * #tj3SetScalingFactor()) or the width of the cropping region (see * #tj3SetCroppingRegion().) If the JPEG image is lossless, then * `destinationWidth` is the JPEG width. * * @param pixelFormat pixel format of the destination image (see @ref * TJPF "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Decompress8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char *dstBuf, int pitch, int pixelFormat); /** * Decompress a 12-bit-per-sample JPEG image into a 12-bit-per-sample * packed-pixel RGB, grayscale, or CMYK image. * * \details \copydetails tj3Decompress8() */ DLLEXPORT int tj3Decompress12(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, short *dstBuf, int pitch, int pixelFormat); /** * Decompress a 16-bit-per-sample lossless JPEG image into a 16-bit-per-sample * packed-pixel RGB, grayscale, or CMYK image. * * \details \copydetails tj3Decompress8() */ DLLEXPORT int tj3Decompress16(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned short *dstBuf, int pitch, int pixelFormat); /** * Decompress an 8-bit-per-sample JPEG image into an 8-bit-per-sample unified * planar YUV image. This function performs JPEG decompression but leaves out * the color conversion step, so a planar YUV image is generated instead of a * packed-pixel image. The @ref TJPARAM "parameters" that describe the JPEG * image will be set when this function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstBuf pointer to a buffer that will receive the unified planar YUV * decompressed image. Use #tj3YUVBufSize() to determine the appropriate size * for this buffer based on the scaled JPEG width and height (see #TJSCALED(), * #TJPARAM_JPEGWIDTH, #TJPARAM_JPEGHEIGHT, and #tj3SetScalingFactor()), row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes will be stored sequentially in the * buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV image (must be a power of * 2.) Setting this parameter to n will cause each row in each plane of the * YUV image to be padded to the nearest multiple of n bytes (1 = unpadded.) * To generate images suitable for X Video, `align` should be set to 4. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressToYUV8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char *dstBuf, int align); /** * Decompress an 8-bit-per-sample JPEG image into separate 8-bit-per-sample Y, * U (Cb), and V (Cr) image planes. This function performs JPEG decompression * but leaves out the color conversion step, so a planar YUV image is generated * instead of a packed-pixel image. The @ref TJPARAM "parameters" that * describe the JPEG image will be set when this function returns. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param jpegBuf pointer to a byte buffer containing the JPEG image to * decompress * * @param jpegSize size of the JPEG image (in bytes) * * @param dstPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if decompressing a grayscale image) that will receive * the decompressed image. These planes can be contiguous or non-contiguous in * memory. Use #tj3YUVPlaneSize() to determine the appropriate size for each * plane based on the scaled JPEG width and height (see #TJSCALED(), * #TJPARAM_JPEGWIDTH, #TJPARAM_JPEGHEIGHT, and #tj3SetScalingFactor()), * strides, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) Refer * to @ref YUVnotes "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV image. Setting the stride for any * plane to 0 is the same as setting it to the scaled plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective scaled plane widths. * You can adjust the strides in order to add an arbitrary amount of row * padding to each plane or to decompress the JPEG image into a subregion of a * larger planar YUV image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecompressToYUVPlanes8(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, unsigned char **dstPlanes, int *strides); /** * Decode an 8-bit-per-sample unified planar YUV image into an 8-bit-per-sample * packed-pixel RGB or grayscale image. This function performs color * conversion (which is accelerated in the libjpeg-turbo implementation) but * does not execute any of the other steps in the JPEG decompression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param srcBuf pointer to a buffer containing a unified planar YUV source * image to be decoded. The size of this buffer should match the value * returned by #tj3YUVBufSize() for the given image width, height, row * alignment, and level of chrominance subsampling (see #TJPARAM_SUBSAMP.) The * Y, U (Cb), and V (Cr) image planes should be stored sequentially in the * source buffer. (Refer to @ref YUVnotes "YUV Image Format Notes".) * * @param align row alignment (in bytes) of the YUV source image (must be a * power of 2.) Setting this parameter to n indicates that each row in each * plane of the YUV source image is padded to the nearest multiple of n bytes * (1 = unpadded.) * * @param dstBuf pointer to a buffer that will receive the packed-pixel decoded * image. This buffer should normally be `pitch * height` bytes in size. * However, you can also use this parameter to decode into a specific region of * a larger buffer. * * @param width width (in pixels) of the source and destination images * * @param pitch bytes per row in the destination image. Normally this should * be set to width * #tjPixelSize[pixelFormat], if the destination * image should be unpadded. (Setting this parameter to 0 is the equivalent of * setting it to width * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decode into a specific region of a * larger buffer. * * @param height height (in pixels) of the source and destination images * * @param pixelFormat pixel format of the destination image (see @ref TJPF * "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecodeYUV8(tjhandle handle, const unsigned char *srcBuf, int align, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat); /** * Decode a set of 8-bit-per-sample Y, U (Cb), and V (Cr) image planes into an * 8-bit-per-sample packed-pixel RGB or grayscale image. This function * performs color conversion (which is accelerated in the libjpeg-turbo * implementation) but does not execute any of the other steps in the JPEG * decompression process. * * @param handle handle to a TurboJPEG instance that has been initialized for * decompression * * @param srcPlanes an array of pointers to Y, U (Cb), and V (Cr) image planes * (or just a Y plane, if decoding a grayscale image) that contain a YUV image * to be decoded. These planes can be contiguous or non-contiguous in memory. * The size of each plane should match the value returned by #tj3YUVPlaneSize() * for the given image width, height, strides, and level of chrominance * subsampling (see #TJPARAM_SUBSAMP.) Refer to @ref YUVnotes * "YUV Image Format Notes" for more details. * * @param strides an array of integers, each specifying the number of bytes per * row in the corresponding plane of the YUV source image. Setting the stride * for any plane to 0 is the same as setting it to the plane width (see * @ref YUVnotes "YUV Image Format Notes".) If `strides` is NULL, then the * strides for all planes will be set to their respective plane widths. You * can adjust the strides in order to specify an arbitrary amount of row * padding in each plane or to decode a subregion of a larger planar YUV image. * * @param dstBuf pointer to a buffer that will receive the packed-pixel decoded * image. This buffer should normally be `pitch * height` bytes in size. * However, you can also use this parameter to decode into a specific region of * a larger buffer. * * @param width width (in pixels) of the source and destination images * * @param pitch bytes per row in the destination image. Normally this should * be set to width * #tjPixelSize[pixelFormat], if the destination * image should be unpadded. (Setting this parameter to 0 is the equivalent of * setting it to width * #tjPixelSize[pixelFormat].) However, you can * also use this parameter to specify the row alignment/padding of the * destination image, to skip rows, or to decode into a specific region of a * larger buffer. * * @param height height (in pixels) of the source and destination images * * @param pixelFormat pixel format of the destination image (see @ref TJPF * "Pixel formats".) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3DecodeYUVPlanes8(tjhandle handle, const unsigned char * const *srcPlanes, const int *strides, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat); /** * Losslessly transform a JPEG image into another JPEG image. Lossless * transforms work by moving the raw DCT coefficients from one JPEG image * structure to another without altering the values of the coefficients. While * this is typically faster than decompressing the image, transforming it, and * re-compressing it, lossless transforms are not free. Each lossless * transform requires reading and performing entropy decoding on all of the * coefficients in the source image, regardless of the size of the destination * image. Thus, this function provides a means of generating multiple * transformed images from the same source or applying multiple transformations * simultaneously, in order to eliminate the need to read the source * coefficients multiple times. * * @param handle handle to a TurboJPEG instance that has been initialized for * lossless transformation * * @param jpegBuf pointer to a byte buffer containing the JPEG source image to * transform * * @param jpegSize size of the JPEG source image (in bytes) * * @param n the number of transformed JPEG images to generate * * @param dstBufs pointer to an array of n byte buffers. `dstBufs[i]` will * receive a JPEG image that has been transformed using the parameters in * `transforms[i]`. TurboJPEG has the ability to reallocate the JPEG * destination buffer to accommodate the size of the transformed JPEG image. * Thus, you can choose to: * -# pre-allocate the JPEG destination buffer with an arbitrary size using * #tj3Alloc() and let TurboJPEG grow the buffer as needed, * -# set `dstBufs[i]` to NULL to tell TurboJPEG to allocate the buffer for * you, or * -# pre-allocate the buffer to a "worst case" size determined by calling * #tj3JPEGBufSize() with the transformed or cropped width and height and the * level of subsampling used in the source image. Under normal circumstances, * this should ensure that the buffer never has to be re-allocated. (Setting * #TJPARAM_NOREALLOC guarantees that it won't be.) Note, however, that there * are some rare cases (such as transforming images with a large amount of * embedded EXIF or ICC profile data) in which the transformed JPEG image will * be larger than the worst-case size, and #TJPARAM_NOREALLOC cannot be used in * those cases. * . * If you choose option 1, then `dstSizes[i]` should be set to the size of your * pre-allocated buffer. In any case, unless you have set #TJPARAM_NOREALLOC, * you should always check `dstBufs[i]` upon return from this function, as it * may have changed. * * @param dstSizes pointer to an array of n size_t variables that will receive * the actual sizes (in bytes) of each transformed JPEG image. If `dstBufs[i]` * points to a pre-allocated buffer, then `dstSizes[i]` should be set to the * size of the buffer. Upon return, `dstSizes[i]` will contain the size of the * transformed JPEG image (in bytes.) * * @param transforms pointer to an array of n #tjtransform structures, each of * which specifies the transform parameters and/or cropping region for the * corresponding transformed JPEG image. * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr() * and #tj3GetErrorCode().) */ DLLEXPORT int tj3Transform(tjhandle handle, const unsigned char *jpegBuf, size_t jpegSize, int n, unsigned char **dstBufs, size_t *dstSizes, const tjtransform *transforms); /** * Destroy a TurboJPEG instance. * * @param handle handle to a TurboJPEG instance. If the handle is NULL, then * this function has no effect. */ DLLEXPORT void tj3Destroy(tjhandle handle); /** * Allocate a byte buffer for use with TurboJPEG. You should always use this * function to allocate the JPEG destination buffer(s) for the compression and * transform functions unless you are disabling automatic buffer (re)allocation * (by setting #TJPARAM_NOREALLOC.) * * @param bytes the number of bytes to allocate * * @return a pointer to a newly-allocated buffer with the specified number of * bytes. * * @see tj3Free() */ DLLEXPORT void *tj3Alloc(size_t bytes); /** * Load an 8-bit-per-sample packed-pixel image from disk into memory. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file containing a packed-pixel image in Windows * BMP or PBMPLUS (PPM/PGM) format. Windows BMP files require 8-bit-per-sample * data precision. If the data precision of the PBMPLUS file does not match * the target data precision, then upconverting or downconverting will be * performed. * * @param width pointer to an integer variable that will receive the width (in * pixels) of the packed-pixel image * * @param align row alignment (in samples) of the packed-pixel buffer to be * returned (must be a power of 2.) Setting this parameter to n will cause all * rows in the buffer to be padded to the nearest multiple of n samples * (1 = unpadded.) * * @param height pointer to an integer variable that will receive the height * (in pixels) of the packed-pixel image * * @param pixelFormat pointer to an integer variable that specifies or will * receive the pixel format of the packed-pixel buffer. The behavior of this * function will vary depending on the value of `*pixelFormat` passed to the * function: * - @ref TJPF_UNKNOWN : The packed-pixel buffer returned by this function will * use the most optimal pixel format for the file type, and `*pixelFormat` will * contain the ID of that pixel format upon successful return from this * function. * - @ref TJPF_GRAY : Only PGM files and 8-bit-per-pixel BMP files with a * grayscale colormap can be loaded. * - @ref TJPF_CMYK : The RGB or grayscale pixels stored in the file will be * converted using a quick & dirty algorithm that is suitable only for testing * purposes. (Proper conversion between CMYK and other formats requires a * color management system.) * - Other @ref TJPF "pixel formats" : The packed-pixel buffer will use the * specified pixel format, and pixel format conversion will be performed if * necessary. * * @return a pointer to a newly-allocated buffer containing the packed-pixel * image, converted to the chosen pixel format and with the chosen row * alignment, or NULL if an error occurred (see #tj3GetErrorStr().) This * buffer should be freed using #tj3Free(). */ DLLEXPORT unsigned char *tj3LoadImage8(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Load a 12-bit-per-sample packed-pixel image from disk into memory. * * \details \copydetails tj3LoadImage8() */ DLLEXPORT short *tj3LoadImage12(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Load a 16-bit-per-sample packed-pixel image from disk into memory. * * \details \copydetails tj3LoadImage8() */ DLLEXPORT unsigned short *tj3LoadImage16(tjhandle handle, const char *filename, int *width, int align, int *height, int *pixelFormat); /** * Save an 8-bit-per-sample packed-pixel image from memory to disk. * * @param handle handle to a TurboJPEG instance * * @param filename name of a file to which to save the packed-pixel image. The * image will be stored in Windows BMP or PBMPLUS (PPM/PGM) format, depending * on the file extension. Windows BMP files require 8-bit-per-sample data * precision. * * @param buffer pointer to a buffer containing a packed-pixel RGB, grayscale, * or CMYK image to be saved * * @param width width (in pixels) of the packed-pixel image * * @param pitch samples per row in the packed-pixel image. Setting this * parameter to 0 is the equivalent of setting it to * width * #tjPixelSize[pixelFormat]. * * @param height height (in pixels) of the packed-pixel image * * @param pixelFormat pixel format of the packed-pixel image (see @ref TJPF * "Pixel formats".) If this parameter is set to @ref TJPF_GRAY, then the * image will be stored in PGM or 8-bit-per-pixel (indexed color) BMP format. * Otherwise, the image will be stored in PPM or 24-bit-per-pixel BMP format. * If this parameter is set to @ref TJPF_CMYK, then the CMYK pixels will be * converted to RGB using a quick & dirty algorithm that is suitable only for * testing purposes. (Proper conversion between CMYK and other formats * requires a color management system.) * * @return 0 if successful, or -1 if an error occurred (see #tj3GetErrorStr().) */ DLLEXPORT int tj3SaveImage8(tjhandle handle, const char *filename, const unsigned char *buffer, int width, int pitch, int height, int pixelFormat); /** * Save a 12-bit-per-sample packed-pixel image from memory to disk. * * \details \copydetails tj3SaveImage8() */ DLLEXPORT int tj3SaveImage12(tjhandle handle, const char *filename, const short *buffer, int width, int pitch, int height, int pixelFormat); /** * Save a 16-bit-per-sample packed-pixel image from memory to disk. * * \details \copydetails tj3SaveImage8() */ DLLEXPORT int tj3SaveImage16(tjhandle handle, const char *filename, const unsigned short *buffer, int width, int pitch, int height, int pixelFormat); /** * Free a byte buffer previously allocated by TurboJPEG. You should always use * this function to free JPEG destination buffer(s) that were automatically * (re)allocated by the compression and transform functions or that were * manually allocated using #tj3Alloc(). * * @param buffer address of the buffer to free. If the address is NULL, then * this function has no effect. * * @see tj3Alloc() */ DLLEXPORT void tj3Free(void *buffer); /** * Returns a descriptive error message explaining why the last command failed. * * @param handle handle to a TurboJPEG instance, or NULL if the error was * generated by a global function (but note that retrieving the error message * for a global function is thread-safe only on platforms that support * thread-local storage.) * * @return a descriptive error message explaining why the last command failed. */ DLLEXPORT char *tj3GetErrorStr(tjhandle handle); /** * Returns a code indicating the severity of the last error. See * @ref TJERR "Error codes". * * @param handle handle to a TurboJPEG instance * * @return a code indicating the severity of the last error. See * @ref TJERR "Error codes". */ DLLEXPORT int tj3GetErrorCode(tjhandle handle); /* Backward compatibility functions and macros (nothing to see here) */ /* TurboJPEG 1.0+ */ #define NUMSUBOPT TJ_NUMSAMP #define TJ_444 TJSAMP_444 #define TJ_422 TJSAMP_422 #define TJ_420 TJSAMP_420 #define TJ_411 TJSAMP_420 #define TJ_GRAYSCALE TJSAMP_GRAY #define TJ_BGR 1 #define TJ_BOTTOMUP TJFLAG_BOTTOMUP #define TJ_FORCEMMX TJFLAG_FORCEMMX #define TJ_FORCESSE TJFLAG_FORCESSE #define TJ_FORCESSE2 TJFLAG_FORCESSE2 #define TJ_ALPHAFIRST 64 #define TJ_FORCESSE3 TJFLAG_FORCESSE3 #define TJ_FASTUPSAMPLE TJFLAG_FASTUPSAMPLE #define TJPAD(width) (((width) + 3) & (~3)) DLLEXPORT unsigned long TJBUFSIZE(int width, int height); DLLEXPORT int tjCompress(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelSize, unsigned char *dstBuf, unsigned long *compressedSize, int jpegSubsamp, int jpegQual, int flags); DLLEXPORT int tjDecompress(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch, int height, int pixelSize, int flags); DLLEXPORT int tjDecompressHeader(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height); DLLEXPORT int tjDestroy(tjhandle handle); DLLEXPORT char *tjGetErrorStr(void); DLLEXPORT tjhandle tjInitCompress(void); DLLEXPORT tjhandle tjInitDecompress(void); /* TurboJPEG 1.1+ */ #define TJ_YUV 512 DLLEXPORT unsigned long TJBUFSIZEYUV(int width, int height, int jpegSubsamp); DLLEXPORT int tjDecompressHeader2(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height, int *jpegSubsamp); DLLEXPORT int tjDecompressToYUV(tjhandle handle, unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int flags); DLLEXPORT int tjEncodeYUV(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelSize, unsigned char *dstBuf, int subsamp, int flags); /* TurboJPEG 1.2+ */ #define TJFLAG_BOTTOMUP 2 #define TJFLAG_FORCEMMX 8 #define TJFLAG_FORCESSE 16 #define TJFLAG_FORCESSE2 32 #define TJFLAG_FORCESSE3 128 #define TJFLAG_FASTUPSAMPLE 256 #define TJFLAG_NOREALLOC 1024 DLLEXPORT unsigned char *tjAlloc(int bytes); DLLEXPORT unsigned long tjBufSize(int width, int height, int jpegSubsamp); DLLEXPORT unsigned long tjBufSizeYUV(int width, int height, int subsamp); DLLEXPORT int tjCompress2(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegSubsamp, int jpegQual, int flags); DLLEXPORT int tjDecompress2(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjEncodeYUV2(tjhandle handle, unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int subsamp, int flags); DLLEXPORT void tjFree(unsigned char *buffer); DLLEXPORT tjscalingfactor *tjGetScalingFactors(int *numscalingfactors); DLLEXPORT tjhandle tjInitTransform(void); DLLEXPORT int tjTransform(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, int n, unsigned char **dstBufs, unsigned long *dstSizes, tjtransform *transforms, int flags); /* TurboJPEG 1.2.1+ */ #define TJFLAG_FASTDCT 2048 #define TJFLAG_ACCURATEDCT 4096 /* TurboJPEG 1.4+ */ DLLEXPORT unsigned long tjBufSizeYUV2(int width, int align, int height, int subsamp); DLLEXPORT int tjCompressFromYUV(tjhandle handle, const unsigned char *srcBuf, int width, int align, int height, int subsamp, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegQual, int flags); DLLEXPORT int tjCompressFromYUVPlanes(tjhandle handle, const unsigned char **srcPlanes, int width, const int *strides, int height, int subsamp, unsigned char **jpegBuf, unsigned long *jpegSize, int jpegQual, int flags); DLLEXPORT int tjDecodeYUV(tjhandle handle, const unsigned char *srcBuf, int align, int subsamp, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjDecodeYUVPlanes(tjhandle handle, const unsigned char **srcPlanes, const int *strides, int subsamp, unsigned char *dstBuf, int width, int pitch, int height, int pixelFormat, int flags); DLLEXPORT int tjDecompressHeader3(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, int *width, int *height, int *jpegSubsamp, int *jpegColorspace); DLLEXPORT int tjDecompressToYUV2(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char *dstBuf, int width, int align, int height, int flags); DLLEXPORT int tjDecompressToYUVPlanes(tjhandle handle, const unsigned char *jpegBuf, unsigned long jpegSize, unsigned char **dstPlanes, int width, int *strides, int height, int flags); DLLEXPORT int tjEncodeYUV3(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char *dstBuf, int align, int subsamp, int flags); DLLEXPORT int tjEncodeYUVPlanes(tjhandle handle, const unsigned char *srcBuf, int width, int pitch, int height, int pixelFormat, unsigned char **dstPlanes, int *strides, int subsamp, int flags); DLLEXPORT int tjPlaneHeight(int componentID, int height, int subsamp); DLLEXPORT unsigned long tjPlaneSizeYUV(int componentID, int width, int stride, int height, int subsamp); DLLEXPORT int tjPlaneWidth(int componentID, int width, int subsamp); /* TurboJPEG 2.0+ */ #define TJFLAG_STOPONWARNING 8192 #define TJFLAG_PROGRESSIVE 16384 DLLEXPORT int tjGetErrorCode(tjhandle handle); DLLEXPORT char *tjGetErrorStr2(tjhandle handle); DLLEXPORT unsigned char *tjLoadImage(const char *filename, int *width, int align, int *height, int *pixelFormat, int flags); DLLEXPORT int tjSaveImage(const char *filename, unsigned char *buffer, int width, int pitch, int height, int pixelFormat, int flags); /* TurboJPEG 2.1+ */ #define TJFLAG_LIMITSCANS 32768 /** * @} */ #ifdef __cplusplus } #endif #endif