--- /dev/null
+1.2.90 (1.3 beta1)
+==================
+
+[1] Added support for additional scaling factors (3/8, 5/8, 3/4, 7/8, 9/8, 5/4,
+11/8, 3/2, 13/8, 7/4, 15/8, and 2) when decompressing. Note that the IDCT will
+not be SIMD-accelerated when using any of these new scaling factors.
+
+[2] The TurboJPEG dynamic library is now versioned. It was not strictly
+necessary to do so, because TurboJPEG uses versioned symbols, and if a function
+changes in an ABI-incompatible way, that function is renamed and a legacy
+function is provided to maintain backward compatibility. However, certain
+Linux distro maintainers will blindly reject any library that is not versioned,
+so this was an attempt to make them happy.
+
+[3] Extended the TurboJPEG Java API so that it can be used to compress a JPEG
+image from and decompress a JPEG image to an arbitrary position in a large
+image buffer.
+
+[4] The tjDecompressToYUV() function now supports the TJFLAG_FASTDCT flag.
+
+[5] The 32-bit supplementary package for amd64 Debian systems now provides
+symlinks in /usr/lib/i386-linux-gnu for the TurboJPEG libraries in /usr/lib32.
+This allows those libraries to be used on MultiArch-compatible systems (such as
+Ubuntu 11 and later) without setting the linker path.
+
+[6] The TurboJPEG Java wrapper should now find the JNI library on Mac systems
+without having to pass -Djava.library.path=/usr/lib to java.
+
+[7] TJBench has been ported to Java to provide a convenient way of validating
+the performance of the TurboJPEG Java API. It can be run with
+'java -cp turbojpeg.jar TJBench'.
+
+[8] cjpeg can now be used to generate JPEG files with the RGB colorspace
+(feature ported from jpeg-8d.)
+
+[9] The width and height in the -crop argument passed to jpegtran can now be
+suffixed with "f" to indicate that, when the upper left corner of the cropping
+region is automatically moved to the nearest iMCU boundary, the bottom right
+corner should be moved by the same amount. In other words, this feature causes
+jpegtran to strictly honor the specified width/height rather than the specified
+bottom right corner (feature ported from jpeg-8d.)
+
++[10] JPEG files using the RGB colorspace can now be decompressed into grayscale
++images (feature ported from jpeg-8d.)
++
+
+1.2.1
+=====
+
+[1] Creating or decoding a JPEG file that uses the RGB colorspace should now
+properly work when the input or output colorspace is one of the libjpeg-turbo
+colorspace extensions.
+
+[2] When libjpeg-turbo was built without SIMD support and merged (non-fancy)
+upsampling was used along with an alpha-enabled colorspace during
+decompression, the unused byte of the decompressed pixels was not being set to
+0xFF. This has been fixed. TJUnitTest has also been extended to test for the
+correct behavior of the colorspace extensions when merged upsampling is used.
+
+[3] Fixed a bug whereby the libjpeg-turbo SSE2 SIMD code would not preserve the
+upper 64 bits of xmm6 and xmm7 on Win64 platforms, which violated the Win64
+calling conventions.
+
+[4] Fixed a regression caused by 1.2.0[6] whereby decompressing corrupt JPEG
+images (specifically, images in which the component count was erroneously set
+to a large value) would cause libjpeg-turbo to segfault.
+
+[5] Worked around a severe performance issue with "Bobcat" (AMD Embedded APU)
+processors. The MASKMOVDQU instruction, which was used by the libjpeg-turbo
+SSE2 SIMD code, is apparently implemented in microcode on AMD processors, and
+it is painfully slow on Bobcat processors in particular. Eliminating the use
+of this instruction improved performance by an order of magnitude on Bobcat
+processors and by a small amount (typically 5%) on AMD desktop processors.
+
+[6] Added SIMD acceleration for performing 4:2:2 upsampling on NEON-capable ARM
+platforms. This speeds up the decompression of 4:2:2 JPEGs by 20-25% on such
+platforms.
+
+[7] Fixed a regression caused by 1.2.0[2] whereby, on Linux/x86 platforms
+running the 32-bit SSE2 SIMD code in libjpeg-turbo, decompressing a 4:2:0 or
+4:2:2 JPEG image into a 32-bit (RGBX, BGRX, etc.) buffer without using fancy
+upsampling would produce several incorrect columns of pixels at the right-hand
+side of the output image if each row in the output image was not evenly
+divisible by 16 bytes.
+
+[8] Fixed an issue whereby attempting to build the SIMD extensions with Xcode
+4.3 on OS X platforms would cause NASM to return numerous errors of the form
+"'%define' expects a macro identifier".
+
+[9] Added flags to the TurboJPEG API that allow the caller to force the use of
+either the fast or the accurate DCT/IDCT algorithms in the underlying codec.
+
+
+1.2.0
+=====
+
+[1] Fixed build issue with YASM on Unix systems (the libjpeg-turbo build system
+was not adding the current directory to the assembler include path, so YASM
+was not able to find jsimdcfg.inc.)
+
+[2] Fixed out-of-bounds read in SSE2 SIMD code that occurred when decompressing
+a JPEG image to a bitmap buffer whose size was not a multiple of 16 bytes.
+This was more of an annoyance than an actual bug, since it did not cause any
+actual run-time problems, but the issue showed up when running libjpeg-turbo in
+valgrind. See http://crbug.com/72399 for more information.
+
+[3] Added a compile-time macro (LIBJPEG_TURBO_VERSION) that can be used to
+check the version of libjpeg-turbo against which an application was compiled.
+
+[4] Added new RGBA/BGRA/ABGR/ARGB colorspace extension constants (libjpeg API)
+and pixel formats (TurboJPEG API), which allow applications to specify that,
+when decompressing to a 4-component RGB buffer, the unused byte should be set
+to 0xFF so that it can be interpreted as an opaque alpha channel.
+
+[5] Fixed regression issue whereby DevIL failed to build against libjpeg-turbo
+because libjpeg-turbo's distributed version of jconfig.h contained an INLINE
+macro, which conflicted with a similar macro in DevIL. This macro is used only
+internally when building libjpeg-turbo, so it was moved into config.h.
+
+[6] libjpeg-turbo will now correctly decompress erroneous CMYK/YCCK JPEGs whose
+K component is assigned a component ID of 1 instead of 4. Although these files
+are in violation of the spec, other JPEG implementations handle them
+correctly.
+
+[7] Added ARM v6 and ARM v7 architectures to libjpeg.a and libturbojpeg.a in
+the official OS X distribution package, so that those libraries can be used to
+build both OS X and iOS applications.
+
+
+1.1.90 (1.2 beta1)
+==================
+
+[1] Added a Java wrapper for the TurboJPEG API. See java/README for more
+details.
+
+[2] The TurboJPEG API can now be used to scale down images during
+decompression.
+
+[3] Added SIMD routines for RGB-to-grayscale color conversion, which
+significantly improves the performance of grayscale JPEG compression from an
+RGB source image.
+
+[4] Improved the performance of the C color conversion routines, which are used
+on platforms for which SIMD acceleration is not available.
+
+[5] Added a function to the TurboJPEG API that performs lossless transforms.
+This function is implemented using the same back end as jpegtran, but it
+performs transcoding entirely in memory and allows multiple transforms and/or
+crop operations to be batched together, so the source coefficients only need to
+be read once. This is useful when generating image tiles from a single source
+JPEG.
+
+[6] Added tests for the new TurboJPEG scaled decompression and lossless
+transform features to tjbench (the TurboJPEG benchmark, formerly called
+"jpgtest".)
+
+[7] Added support for 4:4:0 (transposed 4:2:2) subsampling in TurboJPEG, which
+was necessary in order for it to read 4:2:2 JPEG files that had been losslessly
+transposed or rotated 90 degrees.
+
+[8] All legacy VirtualGL code has been re-factored, and this has allowed
+libjpeg-turbo, in its entirety, to be re-licensed under a BSD-style license.
+
+[9] libjpeg-turbo can now be built with YASM.
+
+[10] Added SIMD acceleration for ARM Linux and iOS platforms that support
+NEON instructions.
+
+[11] Refactored the TurboJPEG C API and documented it using Doxygen. The
+TurboJPEG 1.2 API uses pixel formats to define the size and component order of
+the uncompressed source/destination images, and it includes a more efficient
+version of TJBUFSIZE() that computes a worst-case JPEG size based on the level
+of chrominance subsampling. The refactored implementation of TurboJPEG/OSS
+now uses the libjpeg memory source and destination managers, which allows the
+TurboJPEG compressor to grow the JPEG buffer as necessary.
+
+[12] Eliminated errors in the output of jpegtran on Windows that occurred when
+the application was invoked using I/O redirection
+(jpegtran <input.jpg >output.jpg).
+
+[13] The inclusion of libjpeg v7 and v8 emulation as well as arithmetic coding
+support in libjpeg-turbo v1.1.0 introduced several new error constants in
+jerror.h, and these were mistakenly enabled for all emulation modes, causing
+the error enum in libjpeg-turbo to sometimes have different values than the
+same enum in libjpeg. This represents an ABI incompatibility, and it caused
+problems with rare applications that took specific action based on a particular
+error value. The fix was to include the new error constants conditionally
+based on whether libjpeg v7 or v8 emulation was enabled.
+
+[14] Fixed an issue whereby Windows applications that used libjpeg-turbo would
+fail to compile if the Windows system headers were included before jpeglib.h.
+This issue was caused by a conflict in the definition of the INT32 type.
+
+[15] Fixed 32-bit supplementary package for amd64 Debian systems, which was
+broken by enhancements to the packaging system in 1.1.
+
+[16] When decompressing a JPEG image using an output colorspace of
+JCS_EXT_RGBX, JCS_EXT_BGRX, JCS_EXT_XBGR, or JCS_EXT_XRGB, libjpeg-turbo will
+now set the unused byte to 0xFF, which allows applications to interpret that
+byte as an alpha channel (0xFF = opaque).
+
+
+1.1.1
+=====
+
+[1] Fixed a 1-pixel error in row 0, column 21 of the luminance plane generated
+by tjEncodeYUV().
+
+[2] libjpeg-turbo's accelerated Huffman decoder previously ignored unexpected
+markers found in the middle of the JPEG data stream during decompression. It
+will now hand off decoding of a particular block to the unaccelerated Huffman
+decoder if an unexpected marker is found, so that the unaccelerated Huffman
+decoder can generate an appropriate warning.
+
+[3] Older versions of MinGW64 prefixed symbol names with underscores by
+default, which differed from the behavior of 64-bit Visual C++. MinGW64 1.0
+has adopted the behavior of 64-bit Visual C++ as the default, so to accommodate
+this, the libjpeg-turbo SIMD function names are no longer prefixed with an
+underscore when building with MinGW64. This means that, when building
+libjpeg-turbo with older versions of MinGW64, you will now have to add
+-fno-leading-underscore to the CFLAGS.
+
+[4] Fixed a regression bug in the NSIS script that caused the Windows installer
+build to fail when using the Visual Studio IDE.
+
+[5] Fixed a bug in jpeg_read_coefficients() whereby it would not initialize
+cinfo->image_width and cinfo->image_height if libjpeg v7 or v8 emulation was
+enabled. This specifically caused the jpegoptim program to fail if it was
+linked against a version of libjpeg-turbo that was built with libjpeg v7 or v8
+emulation.
+
+[6] Eliminated excessive I/O overhead that occurred when reading BMP files in
+cjpeg.
+
+[7] Eliminated errors in the output of cjpeg on Windows that occurred when the
+application was invoked using I/O redirection (cjpeg <inputfile >output.jpg).
+
+
+1.1.0
+=====
+
+[1] The algorithm used by the SIMD quantization function cannot produce correct
+results when the JPEG quality is >= 98 and the fast integer forward DCT is
+used. Thus, the non-SIMD quantization function is now used for those cases,
+and libjpeg-turbo should now produce identical output to libjpeg v6b in all
+cases.
+
+[2] Despite the above, the fast integer forward DCT still degrades somewhat for
+JPEG qualities greater than 95, so TurboJPEG/OSS will now automatically use the
+slow integer forward DCT when generating JPEG images of quality 96 or greater.
+This reduces compression performance by as much as 15% for these high-quality
+images but is necessary to ensure that the images are perceptually lossless.
+It also ensures that the library can avoid the performance pitfall created by
+[1].
+
+[3] Ported jpgtest.cxx to pure C to avoid the need for a C++ compiler.
+
+[4] Fixed visual artifacts in grayscale JPEG compression caused by a typo in
+the RGB-to-luminance lookup tables.
+
+[5] The Windows distribution packages now include the libjpeg run-time programs
+(cjpeg, etc.)
+
+[6] All packages now include jpgtest.
+
+[7] The TurboJPEG dynamic library now uses versioned symbols.
+
+[8] Added two new TurboJPEG API functions, tjEncodeYUV() and
+tjDecompressToYUV(), to replace the somewhat hackish TJ_YUV flag.
+
+
+1.0.90 (1.1 beta1)
+==================
+
+[1] Added emulation of the libjpeg v7 and v8 APIs and ABIs. See
+README-turbo.txt for more details. This feature was sponsored by CamTrace SAS.
+
+[2] Created a new CMake-based build system for the Visual C++ and MinGW builds.
+
+[3] Grayscale bitmaps can now be compressed from/decompressed to using the
+TurboJPEG API.
+
+[4] jpgtest can now be used to test decompression performance with existing
+JPEG images.
+
+[5] If the default install prefix (/opt/libjpeg-turbo) is used, then
+'make install' now creates /opt/libjpeg-turbo/lib32 and
+/opt/libjpeg-turbo/lib64 sym links to duplicate the behavior of the binary
+packages.
+
+[6] All symbols in the libjpeg-turbo dynamic library are now versioned, even
+when the library is built with libjpeg v6b emulation.
+
+[7] Added arithmetic encoding and decoding support (can be disabled with
+configure or CMake options)
+
+[8] Added a TJ_YUV flag to the TurboJPEG API, which causes both the compressor
+and decompressor to output planar YUV images.
+
+[9] Added an extended version of tjDecompressHeader() to the TurboJPEG API,
+which allows the caller to determine the type of subsampling used in a JPEG
+image.
+
+[10] Added further protections against invalid Huffman codes.
+
+
+1.0.1
+=====
+
+[1] The Huffman decoder will now handle erroneous Huffman codes (for instance,
+from a corrupt JPEG image.) Previously, these would cause libjpeg-turbo to
+crash under certain circumstances.
+
+[2] Fixed typo in SIMD dispatch routines that was causing 4:2:2 upsampling to
+be used instead of 4:2:0 when decompressing JPEG images using SSE2 code.
+
+[3] configure script will now automatically determine whether the
+INCOMPLETE_TYPES_BROKEN macro should be defined.
+
+
+1.0.0
+=====
+
+[1] 2983700: Further FreeBSD build tweaks (no longer necessary to specify
+--host when configuring on a 64-bit system)
+
+[2] Created sym. links in the Unix/Linux packages so that the TurboJPEG
+include file can always be found in /opt/libjpeg-turbo/include, the 32-bit
+static libraries can always be found in /opt/libjpeg-turbo/lib32, and the
+64-bit static libraries can always be found in /opt/libjpeg-turbo/lib64.
+
+[3] The Unix/Linux distribution packages now include the libjpeg run-time
+programs (cjpeg, etc.) and man pages.
+
+[4] Created a 32-bit supplementary package for amd64 Debian systems, which
+contains just the 32-bit libjpeg-turbo libraries.
+
+[5] Moved the libraries from */lib32 to */lib in the i386 Debian package.
+
+[6] Include distribution package for Cygwin
+
+[7] No longer necessary to specify --without-simd on non-x86 architectures, and
+unit tests now work on those architectures.
+
+
+0.0.93
+======
+
+[1] 2982659, Fixed x86-64 build on FreeBSD systems
+
+[2] 2988188: Added support for Windows 64-bit systems
+
+
+0.0.91
+======
+
+[1] Added documentation to .deb packages
+
+[2] 2968313: Fixed data corruption issues when decompressing large JPEG images
+and/or using buffered I/O with the libjpeg-turbo decompressor
+
+
+0.0.90
+======
+
+Initial release
/*
* jdcolor.c
*
+ * This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
- * This file is part of the Independent JPEG Group's software.
+ * Modified 2011 by Guido Vollbeding.
+ * Modifications:
+ * Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
+ * Copyright (C) 2009, 2011-2012, D. R. Commander.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains output colorspace conversion routines.
#define ONE_HALF ((INT32) 1 << (SCALEBITS-1))
#define FIX(x) ((INT32) ((x) * (1L<<SCALEBITS) + 0.5))
+ /* We allocate one big table for RGB->Y conversion and divide it up into
+ * three parts, instead of doing three alloc_small requests. This lets us
+ * use a single table base address, which can be held in a register in the
+ * inner loops on many machines (more than can hold all three addresses,
+ * anyway).
+ */
+
+ #define R_Y_OFF 0 /* offset to R => Y section */
+ #define G_Y_OFF (1*(MAXJSAMPLE+1)) /* offset to G => Y section */
+ #define B_Y_OFF (2*(MAXJSAMPLE+1)) /* etc. */
+ #define TABLE_SIZE (3*(MAXJSAMPLE+1))
+
+/* Include inline routines for colorspace extensions */
+
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_PIXELSIZE
+
+#define RGB_RED EXT_RGB_RED
+#define RGB_GREEN EXT_RGB_GREEN
+#define RGB_BLUE EXT_RGB_BLUE
+#define RGB_PIXELSIZE EXT_RGB_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extrgb_convert_internal
+#define gray_rgb_convert_internal gray_extrgb_convert_internal
+#define rgb_rgb_convert_internal rgb_extrgb_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+#define RGB_RED EXT_RGBX_RED
+#define RGB_GREEN EXT_RGBX_GREEN
+#define RGB_BLUE EXT_RGBX_BLUE
+#define RGB_ALPHA 3
+#define RGB_PIXELSIZE EXT_RGBX_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extrgbx_convert_internal
+#define gray_rgb_convert_internal gray_extrgbx_convert_internal
+#define rgb_rgb_convert_internal rgb_extrgbx_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_ALPHA
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+#define RGB_RED EXT_BGR_RED
+#define RGB_GREEN EXT_BGR_GREEN
+#define RGB_BLUE EXT_BGR_BLUE
+#define RGB_PIXELSIZE EXT_BGR_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extbgr_convert_internal
+#define gray_rgb_convert_internal gray_extbgr_convert_internal
+#define rgb_rgb_convert_internal rgb_extbgr_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+#define RGB_RED EXT_BGRX_RED
+#define RGB_GREEN EXT_BGRX_GREEN
+#define RGB_BLUE EXT_BGRX_BLUE
+#define RGB_ALPHA 3
+#define RGB_PIXELSIZE EXT_BGRX_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extbgrx_convert_internal
+#define gray_rgb_convert_internal gray_extbgrx_convert_internal
+#define rgb_rgb_convert_internal rgb_extbgrx_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_ALPHA
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+#define RGB_RED EXT_XBGR_RED
+#define RGB_GREEN EXT_XBGR_GREEN
+#define RGB_BLUE EXT_XBGR_BLUE
+#define RGB_ALPHA 0
+#define RGB_PIXELSIZE EXT_XBGR_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extxbgr_convert_internal
+#define gray_rgb_convert_internal gray_extxbgr_convert_internal
+#define rgb_rgb_convert_internal rgb_extxbgr_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_ALPHA
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+#define RGB_RED EXT_XRGB_RED
+#define RGB_GREEN EXT_XRGB_GREEN
+#define RGB_BLUE EXT_XRGB_BLUE
+#define RGB_ALPHA 0
+#define RGB_PIXELSIZE EXT_XRGB_PIXELSIZE
+#define ycc_rgb_convert_internal ycc_extxrgb_convert_internal
+#define gray_rgb_convert_internal gray_extxrgb_convert_internal
+#define rgb_rgb_convert_internal rgb_extxrgb_convert_internal
+#include "jdcolext.c"
+#undef RGB_RED
+#undef RGB_GREEN
+#undef RGB_BLUE
+#undef RGB_ALPHA
+#undef RGB_PIXELSIZE
+#undef ycc_rgb_convert_internal
+#undef gray_rgb_convert_internal
+#undef rgb_rgb_convert_internal
+
+
/*
* Initialize tables for YCC->RGB colorspace conversion.
*/
/**************** Cases other than YCbCr -> RGB **************/
-/*
- * No colorspace change, but conversion from separate-planes
- * to interleaved representation.
- */
-
-METHODDEF(void)
-rgb_convert (j_decompress_ptr cinfo,
- JSAMPIMAGE input_buf, JDIMENSION input_row,
- JSAMPARRAY output_buf, int num_rows)
-{
- register JSAMPROW outptr;
- register JSAMPROW inptr0, inptr1, inptr2;
- register JDIMENSION col;
- JDIMENSION num_cols = cinfo->output_width;
-
- while (--num_rows >= 0) {
- inptr0 = input_buf[0][input_row];
- inptr1 = input_buf[1][input_row];
- inptr2 = input_buf[2][input_row];
- input_row++;
- outptr = *output_buf++;
- for (col = 0; col < num_cols; col++) {
- /* We can dispense with GETJSAMPLE() here */
- outptr[RGB_RED] = inptr0[col];
- outptr[RGB_GREEN] = inptr1[col];
- outptr[RGB_BLUE] = inptr2[col];
- outptr += RGB_PIXELSIZE;
- }
- }
-}
-
-
+ /*
+ * Initialize for RGB->grayscale colorspace conversion.
+ */
+
+ LOCAL(void)
+ build_rgb_y_table (j_decompress_ptr cinfo)
+ {
+ my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
+ INT32 * rgb_y_tab;
+ INT32 i;
+
+ /* Allocate and fill in the conversion tables. */
+ cconvert->rgb_y_tab = rgb_y_tab = (INT32 *)
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+ (TABLE_SIZE * SIZEOF(INT32)));
+
+ for (i = 0; i <= MAXJSAMPLE; i++) {
+ rgb_y_tab[i+R_Y_OFF] = FIX(0.29900) * i;
+ rgb_y_tab[i+G_Y_OFF] = FIX(0.58700) * i;
+ rgb_y_tab[i+B_Y_OFF] = FIX(0.11400) * i + ONE_HALF;
+ }
+ }
+
+
+ /*
+ * Convert RGB to grayscale.
+ */
+
+ METHODDEF(void)
+ rgb_gray_convert (j_decompress_ptr cinfo,
+ JSAMPIMAGE input_buf, JDIMENSION input_row,
+ JSAMPARRAY output_buf, int num_rows)
+ {
+ my_cconvert_ptr cconvert = (my_cconvert_ptr) cinfo->cconvert;
+ register int r, g, b;
+ register INT32 * ctab = cconvert->rgb_y_tab;
+ register JSAMPROW outptr;
+ register JSAMPROW inptr0, inptr1, inptr2;
+ register JDIMENSION col;
+ JDIMENSION num_cols = cinfo->output_width;
+
+ while (--num_rows >= 0) {
+ inptr0 = input_buf[0][input_row];
+ inptr1 = input_buf[1][input_row];
+ inptr2 = input_buf[2][input_row];
+ input_row++;
+ outptr = *output_buf++;
+ for (col = 0; col < num_cols; col++) {
+ r = GETJSAMPLE(inptr0[col]);
+ g = GETJSAMPLE(inptr1[col]);
+ b = GETJSAMPLE(inptr2[col]);
+ /* Y */
+ outptr[col] = (JSAMPLE)
+ ((ctab[r+R_Y_OFF] + ctab[g+G_Y_OFF] + ctab[b+B_Y_OFF])
+ >> SCALEBITS);
+ }
+ }
+ }
+
+
/*
* Color conversion for no colorspace change: just copy the data,
* converting from separate-planes to interleaved representation.