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, and it is thus possible for a very high-quality JPEG image with very high-frequency content to expand rather than compress when converted to the JPEG format. Such images represent a very rare corner case, but since there is no way to predict the size of a JPEG image prior to compression, the corner case has to be handled.
| width | width of the image (in pixels) |
| height | height of the image (in pixels) |
| width | width of the image (in pixels) |
| height | height of the image (in pixels) |
| jpegSubsamp | the level of chrominance subsampling to be used when generating the JPEG image (see Chrominance subsampling options.) |
The size of the buffer (in bytes) required to hold a YUV planar image with the given parameters.
| width | width of the image (in pixels) |
| pad | the width of each line in each plane of the image is padded to the nearest multiple of this number of bytes (must be a power of 2.) |
| height | height of the image (in pixels) |
| width | width of the image (in pixels) |
| pad | the width of each line in each plane of the image is padded to the nearest multiple of this number of bytes (must be a power of 2.) |
| height | height of the image (in pixels) |
| subsamp | level of chrominance subsampling in the image (see Chrominance subsampling options.) |
Compress an RGB, grayscale, or CMYK image into a JPEG image.
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB, grayscale, or CMYK pixels to be compressed |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB, grayscale, or CMYK pixels to be compressed |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| jpegBuf | address of a pointer to an image 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:
*jpegSize should be set to the size of your pre-allocated buffer. In any case, unless you have set TJFLAG_NOREALLOC, you should always check *jpegBuf upon return from this function, as it may have changed. |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegSubsamp | the level of chrominance subsampling to be used when generating the JPEG image (see Chrominance subsampling options.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegSubsamp | the level of chrominance subsampling to be used when generating the JPEG image (see Chrominance subsampling options.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
Compress a YUV planar image into a JPEG image.
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing a YUV planar image to be compressed. The size of this buffer should match the value returned by tjBufSizeYUV2() for the given image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be stored sequentially in the source buffer (refer to YUV Image Format Notes.) |
| 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 within TurboJPEG. |
| pad | the line padding used in the source image. For instance, if each line in each plane of the YUV image is padded to the nearest multiple of 4 bytes, then pad should be set to 4. |
| 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 within TurboJPEG. |
| subsamp | the level of chrominance subsampling used in the source image (see Chrominance subsampling options.) |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing a YUV planar image to be compressed. The size of this buffer should match the value returned by tjBufSizeYUV2() for the given image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be stored sequentially in the source buffer (refer to YUV Image Format Notes.) |
| 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 within TurboJPEG. |
| pad | the line padding used in the source image. For instance, if each line in each plane of the YUV image is padded to the nearest multiple of 4 bytes, then pad should be set to 4. |
| 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 within TurboJPEG. |
| subsamp | the level of chrominance subsampling used in the source image (see Chrominance subsampling options.) |
| jpegBuf | address of a pointer to an image 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:
*jpegSize should be set to the size of your pre-allocated buffer. In any case, unless you have set TJFLAG_NOREALLOC, you should always check *jpegBuf upon return from this function, as it may have changed. |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
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| @@ -1185,20 +1185,20 @@ If you choose option 1, |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| 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 image to be compressed. These planes can be contiguous or non-contiguous in memory. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| 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 within TurboJPEG. |
| strides | an array of integers, each specifying the number of bytes per line 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 component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to specify an arbitrary amount of line padding in each plane or to create a JPEG image from a subregion of a larger YUV planar image. |
| 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 within TurboJPEG. |
| subsamp | the level of chrominance subsampling used in the source image (see Chrominance subsampling options.) |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| 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 image to be compressed. These planes can be contiguous or non-contiguous in memory. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| 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 within TurboJPEG. |
| strides | an array of integers, each specifying the number of bytes per line 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 component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to specify an arbitrary amount of line padding in each plane or to create a JPEG image from a subregion of a larger YUV planar image. |
| 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 within TurboJPEG. |
| subsamp | the level of chrominance subsampling used in the source image (see Chrominance subsampling options.) |
| jpegBuf | address of a pointer to an image 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:
*jpegSize should be set to the size of your pre-allocated buffer. In any case, unless you have set TJFLAG_NOREALLOC, you should always check *jpegBuf upon return from this function, as it may have changed. |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| jpegSize | pointer to an unsigned long variable that holds the size of the JPEG image 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.) |
| jpegQual | the image quality of the generated JPEG image (1 = worst, 100 = best) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
This function uses the accelerated color conversion routines in the underlying codec but does not execute any of the other steps in the JPEG decompression process.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| srcBuf | pointer to an image buffer containing a YUV planar image to be decoded. The size of this buffer should match the value returned by tjBufSizeYUV2() for the given image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be stored sequentially in the source buffer (refer to YUV Image Format Notes.) |
| pad | Use this parameter to specify that the width of each line in each plane of the YUV source image is padded to the nearest multiple of this number of bytes (must be a power of 2.) |
| subsamp | the level of chrominance subsampling used in the YUV source image (see Chrominance subsampling options.) |
| dstBuf | pointer to an image buffer that will receive the decoded image. This buffer should normally be pitch * height bytes in size, but the dstBuf pointer can also be used to decode into a specific region of a larger buffer. |
| width | width (in pixels) of the source and destination images |
| pitch | bytes per line of the destination image. Normally, this should be width * tjPixelSize[pixelFormat] if the destination image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the destination image should be padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source and destination images |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| srcBuf | pointer to an image buffer containing a YUV planar image to be decoded. The size of this buffer should match the value returned by tjBufSizeYUV2() for the given image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes should be stored sequentially in the source buffer (refer to YUV Image Format Notes.) |
| pad | Use this parameter to specify that the width of each line in each plane of the YUV source image is padded to the nearest multiple of this number of bytes (must be a power of 2.) |
| subsamp | the level of chrominance subsampling used in the YUV source image (see Chrominance subsampling options.) |
| dstBuf | pointer to an image buffer that will receive the decoded image. This buffer should normally be pitch * height bytes in size, but the dstBuf pointer can also be used to decode into a specific region of a larger buffer. |
| width | width (in pixels) of the source and destination images |
| pitch | bytes per line of the destination image. Normally, this should be width * tjPixelSize[pixelFormat] if the destination image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the destination image should be padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source and destination images |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
This function uses the accelerated color conversion routines in the underlying codec but does not execute any of the other steps in the JPEG decompression process.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| 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. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| strides | an array of integers, each specifying the number of bytes per line 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 component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to specify an arbitrary amount of line padding in each plane or to decode a subregion of a larger YUV planar image. |
| subsamp | the level of chrominance subsampling used in the YUV source image (see Chrominance subsampling options.) |
| dstBuf | pointer to an image buffer that will receive the decoded image. This buffer should normally be pitch * height bytes in size, but the dstBuf pointer can also be used to decode into a specific region of a larger buffer. |
| width | width (in pixels) of the source and destination images |
| pitch | bytes per line of the destination image. Normally, this should be width * tjPixelSize[pixelFormat] if the destination image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the destination image should be padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source and destination images |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| 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. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| strides | an array of integers, each specifying the number of bytes per line 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 component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to specify an arbitrary amount of line padding in each plane or to decode a subregion of a larger YUV planar image. |
| subsamp | the level of chrominance subsampling used in the YUV source image (see Chrominance subsampling options.) |
| dstBuf | pointer to an image buffer that will receive the decoded image. This buffer should normally be pitch * height bytes in size, but the dstBuf pointer can also be used to decode into a specific region of a larger buffer. |
| width | width (in pixels) of the source and destination images |
| pitch | bytes per line of the destination image. Normally, this should be width * tjPixelSize[pixelFormat] if the destination image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the destination image should be padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source and destination images |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
Decompress a JPEG image to an RGB, grayscale, or CMYK image.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| dstBuf | pointer to an image buffer that will receive the decompressed image. This buffer should normally be pitch * scaledHeight bytes in size, where scaledHeight can be determined by calling TJSCALED() with the JPEG image height and one of the scaling factors returned by tjGetScalingFactors(). The dstBuf pointer may also be used to decompress into a specific region of a larger buffer. |
| width | desired width (in pixels) of the destination image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. |
| pitch | bytes per line of the destination image. Normally, this is scaledWidth * tjPixelSize[pixelFormat] if the decompressed image is unpadded, else TJPAD(scaledWidth * tjPixelSize[pixelFormat]) if each line of the decompressed image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. (NOTE: scaledWidth can be determined by calling TJSCALED() with the JPEG image width and one of the scaling factors returned by tjGetScalingFactors().) You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to scaledWidth * tjPixelSize[pixelFormat]. |
| height | desired height (in pixels) of the destination image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| dstBuf | pointer to an image buffer that will receive the decompressed image. This buffer should normally be pitch * scaledHeight bytes in size, where scaledHeight can be determined by calling TJSCALED() with the JPEG image height and one of the scaling factors returned by tjGetScalingFactors(). The dstBuf pointer may also be used to decompress into a specific region of a larger buffer. |
| width | desired width (in pixels) of the destination image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. |
| pitch | bytes per line of the destination image. Normally, this is scaledWidth * tjPixelSize[pixelFormat] if the decompressed image is unpadded, else TJPAD(scaledWidth * tjPixelSize[pixelFormat]) if each line of the decompressed image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. (NOTE: scaledWidth can be determined by calling TJSCALED() with the JPEG image width and one of the scaling factors returned by tjGetScalingFactors().) You can also be clever and use the pitch parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to scaledWidth * tjPixelSize[pixelFormat]. |
| height | desired height (in pixels) of the destination image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. |
| pixelFormat | pixel format of the destination image (see Pixel formats.) |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
Retrieve information about a JPEG image without decompressing it.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing a JPEG image |
| jpegSize | size of the JPEG image (in bytes) |
| width | pointer to an integer variable that will receive the width (in pixels) of the JPEG image |
| height | pointer to an integer variable that will receive the height (in pixels) of the JPEG image |
| jpegSubsamp | pointer to an integer variable that will receive the level of chrominance subsampling used when compressing the JPEG image (see Chrominance subsampling options.) |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing a JPEG image |
| jpegSize | size of the JPEG image (in bytes) |
| width | pointer to an integer variable that will receive the width (in pixels) of the JPEG image |
| height | pointer to an integer variable that will receive the height (in pixels) of the JPEG image |
| jpegSubsamp | pointer to an integer variable that will receive the level of chrominance subsampling used when compressing the JPEG image (see Chrominance subsampling options.) |
| jpegColorspace | pointer to an integer variable that will receive one of the JPEG colorspace constants, indicating the colorspace of the JPEG image (see JPEG colorspaces.) |
*jpegSize should be set to the size of your
This function performs JPEG decompression but leaves out the color conversion step, so a planar YUV image is generated instead of an RGB image.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| dstBuf | pointer to an image buffer that will receive the YUV image. Use tjBufSizeYUV2() to determine the appropriate size for this buffer based on the image width, height, padding, and level of subsampling. The Y, U (Cb), and V (Cr) image planes will be stored sequentially in the buffer (refer to YUV Image Format Notes.) |
| width | desired width (in pixels) of the YUV image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. If the scaled width is not an even multiple of the MCU block width (see tjMCUWidth), then an intermediate buffer copy will be performed within TurboJPEG. |
| pad | the width of each line in each plane of the YUV image will be padded to the nearest multiple of this number of bytes (must be a power of 2.) To generate images suitable for X Video, pad should be set to 4. |
| height | desired height (in pixels) of the YUV image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. If the scaled height is not an even multiple of the MCU block height (see tjMCUHeight), then an intermediate buffer copy will be performed within TurboJPEG. |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| dstBuf | pointer to an image buffer that will receive the YUV image. Use tjBufSizeYUV2() to determine the appropriate size for this buffer based on the image width, height, padding, and level of subsampling. The Y, U (Cb), and V (Cr) image planes will be stored sequentially in the buffer (refer to YUV Image Format Notes.) |
| width | desired width (in pixels) of the YUV image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. If the scaled width is not an even multiple of the MCU block width (see tjMCUWidth), then an intermediate buffer copy will be performed within TurboJPEG. |
| pad | the width of each line in each plane of the YUV image will be padded to the nearest multiple of this number of bytes (must be a power of 2.) To generate images suitable for X Video, pad should be set to 4. |
| height | desired height (in pixels) of the YUV image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. If the scaled height is not an even multiple of the MCU block height (see tjMCUHeight), then an intermediate buffer copy will be performed within TurboJPEG. |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
This function performs JPEG decompression but leaves out the color conversion step, so a planar YUV image is generated instead of an RGB image.
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| 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 YUV image. These planes can be contiguous or non-contiguous in memory. Each plane should be at least {component stride} * {scaled component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| width | desired width (in pixels) of the YUV image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. If the scaled width is not an even multiple of the MCU block width (see tjMCUWidth), then an intermediate buffer copy will be performed within TurboJPEG. |
| strides | an array of integers, each specifying the number of bytes per line in the corresponding plane of the output image. Setting the stride for any plane to 0 is the same as setting it to the scaled component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective scaled component widths. You can adjust the strides in order to add an arbitrary amount of line padding to each plane or to decompress the JPEG image into a subregion of a larger YUV planar image. |
| height | desired height (in pixels) of the YUV image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. If the scaled height is not an even multiple of the MCU block height (see tjMCUHeight), then an intermediate buffer copy will be performed within TurboJPEG. |
| handle | a handle to a TurboJPEG decompressor or transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to decompress |
| jpegSize | size of the JPEG image (in bytes) |
| 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 YUV image. These planes can be contiguous or non-contiguous in memory. Each plane should be at least {component stride} * {scaled component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| width | desired width (in pixels) of the YUV image. If this is different than the width of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired width. If width is set to 0, then only the height will be considered when determining the scaled image size. If the scaled width is not an even multiple of the MCU block width (see tjMCUWidth), then an intermediate buffer copy will be performed within TurboJPEG. |
| strides | an array of integers, each specifying the number of bytes per line in the corresponding plane of the output image. Setting the stride for any plane to 0 is the same as setting it to the scaled component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective scaled component widths. You can adjust the strides in order to add an arbitrary amount of line padding to each plane or to decompress the JPEG image into a subregion of a larger YUV planar image. |
| height | desired height (in pixels) of the YUV image. If this is different than the height of the JPEG image being decompressed, then TurboJPEG will use scaling in the JPEG decompressor to generate the largest possible image that will fit within the desired height. If height is set to 0, then only the width will be considered when determining the scaled image size. If the scaled height is not an even multiple of the MCU block height (see tjMCUHeight), then an intermediate buffer copy will be performed within TurboJPEG. |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
This function uses the accelerated color conversion routines in the underlying codec but does not execute any of the other steps in the JPEG compression process.
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB or grayscale pixels to be encoded |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| dstBuf | pointer to an image buffer that will receive the YUV image. Use tjBufSizeYUV2() to determine the appropriate size for this buffer based on the image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes will be stored sequentially in the buffer (refer to YUV Image Format Notes.) |
| pad | the width of each line in each plane of the YUV image will be padded to the nearest multiple of this number of bytes (must be a power of 2.) To generate images suitable for X Video, pad should be set to 4. |
| subsamp | the level of chrominance subsampling to be used when generating the YUV image (see Chrominance subsampling options.) To generate images suitable for X Video, subsamp should be set to TJSAMP_420. This produces an image compatible with the I420 (AKA "YUV420P") format. |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB or grayscale pixels to be encoded |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| dstBuf | pointer to an image buffer that will receive the YUV image. Use tjBufSizeYUV2() to determine the appropriate size for this buffer based on the image width, height, padding, and level of chrominance subsampling. The Y, U (Cb), and V (Cr) image planes will be stored sequentially in the buffer (refer to YUV Image Format Notes.) |
| pad | the width of each line in each plane of the YUV image will be padded to the nearest multiple of this number of bytes (must be a power of 2.) To generate images suitable for X Video, pad should be set to 4. |
| subsamp | the level of chrominance subsampling to be used when generating the YUV image (see Chrominance subsampling options.) To generate images suitable for X Video, subsamp should be set to TJSAMP_420. This produces an image compatible with the I420 (AKA "YUV420P") format. |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
This function uses the accelerated color conversion routines in the underlying codec but does not execute any of the other steps in the JPEG compression process.
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB or grayscale pixels to be encoded |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| 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. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| strides | an array of integers, each specifying the number of bytes per line in the corresponding plane of the output image. Setting the stride for any plane to 0 is the same as setting it to the component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to add an arbitrary amount of line padding to each plane or to encode an RGB or grayscale image into a subregion of a larger YUV planar image. |
| subsamp | the level of chrominance subsampling to be used when generating the YUV image (see Chrominance subsampling options.) To generate images suitable for X Video, subsamp should be set to TJSAMP_420. This produces an image compatible with the I420 (AKA "YUV420P") format. |
| handle | a handle to a TurboJPEG compressor or transformer instance |
| srcBuf | pointer to an image buffer containing RGB or grayscale pixels to be encoded |
| width | width (in pixels) of the source image |
| pitch | bytes per line of the source image. Normally, this should be width * tjPixelSize[pixelFormat] if the image is unpadded, or TJPAD(width * tjPixelSize[pixelFormat]) if each line of the image is padded to the nearest 32-bit boundary, as is the case for Windows bitmaps. You can also be clever and use this parameter to skip lines, etc. Setting this parameter to 0 is the equivalent of setting it to width * tjPixelSize[pixelFormat]. |
| height | height (in pixels) of the source image |
| pixelFormat | pixel format of the source image (see Pixel formats.) |
| 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. Each plane should be at least {component stride} * {component height} bytes in size. (See below for a description of stride, and refer to YUV Image Format Notes for a description of component height.) |
| strides | an array of integers, each specifying the number of bytes per line in the corresponding plane of the output image. Setting the stride for any plane to 0 is the same as setting it to the component width for the plane. If stride is NULL, then the strides for all planes will be set to their respective component widths. You can adjust the strides in order to add an arbitrary amount of line padding to each plane or to encode an RGB or grayscale image into a subregion of a larger YUV planar image. |
| subsamp | the level of chrominance subsampling to be used when generating the YUV image (see Chrominance subsampling options.) To generate images suitable for X Video, subsamp should be set to TJSAMP_420. This produces an image compatible with the I420 (AKA "YUV420P") format. |
| flags | the bitwise OR of one or more of the flags. |
*jpegSize should be set to the size of your
Lossless transforms work by moving the raw 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 Huffman 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.
| handle | a handle to a TurboJPEG transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to transform |
| jpegSize | size of the JPEG image (in bytes) |
| n | the number of transformed JPEG images to generate |
| handle | a handle to a TurboJPEG transformer instance |
| jpegBuf | pointer to a buffer containing the JPEG image to transform |
| jpegSize | size of the JPEG image (in bytes) |
| n | the number of transformed JPEG images to generate |
| dstBufs | pointer to an array of n image 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 buffer to accommodate the size of the JPEG image. Thus, you can choose to:
dstSizes[i] should be set to the size of your pre-allocated buffer. In any case, unless you have set TJFLAG_NOREALLOC, you should always check dstBufs[i] upon return from this function, as it may have changed. |
| dstSizes | pointer to an array of n unsigned long 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 JPEG image (in bytes.) |
| transforms | pointer to an array of n tjtransform structures, each of which specifies the transform parameters and/or cropping region for the corresponding transformed output image. |
| dstSizes | pointer to an array of n unsigned long 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 JPEG image (in bytes.) |
| transforms | pointer to an array of n tjtransform structures, each of which specifies the transform parameters and/or cropping region for the corresponding transformed output image. |
| flags | the bitwise OR of one or more of the flags. |
This allows for custom filters or other transformations to be applied in the frequency domain.
| 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.) |
| 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. |
| planeRegion | tjregion structure containing the width and height of the component plane to which coeffs belongs |
| 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.) |
| 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 tjTransform(). |
| 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.) |
| 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. |
| planeRegion | tjregion structure containing the width and height of the component plane to which coeffs belongs |
| 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.) |
| 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 tjTransform(). |
| transform | a pointer to a tjtransform structure that specifies the parameters and/or cropping region for this transform |