diff --git a/libjpeg-turbo.spec b/libjpeg-turbo.spec index 2ced05a..c03017d 100644 --- a/libjpeg-turbo.spec +++ b/libjpeg-turbo.spec @@ -1,6 +1,6 @@ Name: libjpeg-turbo Version: 1.0.1 -Release: 2%{?dist} +Release: 3%{?dist} Summary: A MMX/SSE2 accelerated library for manipulating JPEG image files Group: System Environment/Libraries @@ -21,6 +21,8 @@ Obsoletes: libjpeg < 6b-47 # java-1.6.0-openjdk (#rh607554) -- atkac Provides: libjpeg = 6b-47 +Patch0: libjpeg-turbo10-rh639672.patch + %description The libjpeg-turbo package contains a library of functions for manipulating JPEG images @@ -70,6 +72,8 @@ JPEG images %prep %setup -q +%patch0 -p1 -b .rh639672 + %build autoreconf -fiv @@ -131,6 +135,9 @@ rm -rf $RPM_BUILD_ROOT %{_libdir}/libjpeg.a %changelog +* Fri Oct 29 2010 Adam Tkac 1.0.1-3 +- add support for arithmetic coded files into decoder (#639672) + * Wed Sep 29 2010 jkeating - 1.0.1-2 - Rebuilt for gcc bug 634757 diff --git a/libjpeg-turbo10-rh639672.patch b/libjpeg-turbo10-rh639672.patch new file mode 100644 index 0000000..e862d0d --- /dev/null +++ b/libjpeg-turbo10-rh639672.patch @@ -0,0 +1,1283 @@ +From 195345e454d3df7ff9c07c3d36881ec52e789af2 Mon Sep 17 00:00:00 2001 +From: Mukund Sivaraman +Date: Sun, 3 Oct 2010 12:23:41 +0530 +Subject: [PATCH] Add support for decoding arithmetic coded content + +This is based on a patch by Guido Vollbeding , which +included code to both encode and decode arithmetic coded content. + +This patch only adds the decoding portion. No new arithmetic coded +content can be produced, but existing arithmetic coded content can +be decoded. + +libjpeg-turbo with this patch has been tested with some arithmetic +coded images (digital photographs). +--- + Makefile.am | 17 +- + README.arithmetic | 215 +++++++++++++++ + jaricom.c | 149 +++++++++++ + jdarith.c | 762 +++++++++++++++++++++++++++++++++++++++++++++++++++++ + jdmaster.c | 2 +- + jdtrans.c | 2 +- + jerror.h | 2 + + jmorecfg.h | 2 +- + jpegint.h | 2 + + 9 files changed, 1142 insertions(+), 11 deletions(-) + create mode 100644 README.arithmetic + create mode 100644 jaricom.c + create mode 100644 jdarith.c + +diff --git a/Makefile.am b/Makefile.am +index f8552ea..1eee598 100644 +--- a/Makefile.am ++++ b/Makefile.am +@@ -7,14 +7,15 @@ nodist_include_HEADERS = jconfig.h + HDRS = jchuff.h jdct.h jdhuff.h jerror.h jinclude.h jmemsys.h jmorecfg.h \ + jpegint.h jpeglib.h jversion.h jsimd.h jsimddct.h + +-libjpeg_la_SOURCES = $(HDRS) jcapimin.c jcapistd.c jccoefct.c jccolor.c \ +- jcdctmgr.c jchuff.c jcinit.c jcmainct.c jcmarker.c jcmaster.c \ +- jcomapi.c jcparam.c jcphuff.c jcprepct.c jcsample.c jctrans.c \ +- jdapimin.c jdapistd.c jdatadst.c jdatasrc.c jdcoefct.c jdcolor.c \ +- jddctmgr.c jdhuff.c jdinput.c jdmainct.c jdmarker.c jdmaster.c \ +- jdmerge.c jdphuff.c jdpostct.c jdsample.c jdtrans.c jerror.c \ +- jfdctflt.c jfdctfst.c jfdctint.c jidctflt.c jidctfst.c jidctint.c \ +- jidctred.c jquant1.c jquant2.c jutils.c jmemmgr.c jmemnobs.c ++libjpeg_la_SOURCES = $(HDRS) jaricom.c jcapimin.c jcapistd.c \ ++ jccoefct.c jccolor.c jcdctmgr.c jchuff.c jcinit.c jcmainct.c \ ++ jcmarker.c jcmaster.c jcomapi.c jcparam.c jcphuff.c jcprepct.c \ ++ jcsample.c jctrans.c jdapimin.c jdapistd.c jdarith.c \ ++ jdatadst.c jdatasrc.c jdcoefct.c jdcolor.c jddctmgr.c jdhuff.c \ ++ jdinput.c jdmainct.c jdmarker.c jdmaster.c jdmerge.c jdphuff.c \ ++ jdpostct.c jdsample.c jdtrans.c jerror.c jfdctflt.c jfdctfst.c \ ++ jfdctint.c jidctflt.c jidctfst.c jidctint.c jidctred.c \ ++ jquant1.c jquant2.c jutils.c jmemmgr.c jmemnobs.c + + libturbojpeg_la_SOURCES = $(libjpeg_la_SOURCES) turbojpegl.c turbojpeg.h \ + turbojpeg-mapfile +diff --git a/README.arithmetic b/README.arithmetic +new file mode 100644 +index 0000000..0dd3b9a +--- /dev/null ++++ b/README.arithmetic +@@ -0,0 +1,215 @@ ++JPEG arithmetic encoding and decoding portable software implementation ++====================================================================== ++ ++Release of 28-Mar-98 by Guido Vollbeding ++============================================================= ++ ++Primary URLs: ++ ++ http://sylvana.net/jpeg-ari/ ++ (directory containing the actual archive files:) ++ ++ http://sylvana.net/jpeg-ari/jpeg-ari-28mar98.tar.gz ++ ++ http://sylvana.net/jpeg-ari/jpeg-ari.zip ++ ++ ++DISCLAIMER ++========== ++ ++This package is distributed in the hope that it will be useful, ++but WITHOUT ANY WARRANTY; without even the implied warranty of ++MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. ++ ++It is possible that certain products which can be built using this ++software modules might form inventions protected by patent rights in ++some countries (e.g. by patents about arithmetic coding algorithms ++owned by IBM and AT&T in the USA). Provision of this software by the ++author does NOT include any licenses for any patents. ++In those countries where a patent license is required for certain ++applications of this software modules, you will have to obtain such ++a license yourself. ++ ++See Annex L in the JPEG spec for further information ++and a list of relevant patents. ++ ++ ++What is it? ++=========== ++ ++This is my implementation of the arithmetic encoding and decoding ++back-end for JPEG as specified in the ++ ++ ISO/IEC International Standard 10918-1 and CCITT Recommendation ++ ITU-T T.81, "Information Technology - Digital Compression and ++ Coding of Continuous-tone Still Images, Part 1: Requirements ++ and Guidelines". ++ ++Arithmetic coding is a state-of-the-art lossless entropy data ++compression method which offers better compression performance ++than the well-established Huffman entropy coding process. ++ ++The JPEG standard specifies a particular arithmetic coding scheme ++to be used optionally as alternative to Huffman coding. ++ ++ ++Who needs it? ++============= ++ ++This package might be of interest for people who are looking for ++enhanced state-of-the-art image compression technologies. ++ ++It is intended to provide a reasonable tool for experimental, ++comparison and evaluation purposes. ++ ++See the Disclaimer above for restricted conditions of usage. ++ ++ ++How does it work? ++================= ++ ++This distribution is organized as add-on to the widespread ++Independent JPEG Group's JPEG software. ++ ++Thus, once you managed to install the IJG software distribution ++successfully, there should be no additional problems (portability ++issues etc.) to incorporate this package into the library, ++and usage is straightforward. ++ ++Transcode given JPEG files simply with a command like ++ ++ jpegtran -arithmetic [-progressive] < orig.jpg > arit.jpg ++ ++into an arithmetic coded version LOSSLESSLY! Since there are ++practically no applications in existence which can handle such ++files, you can only transform it back with the same tool ++ ++ jpegtran [-optimize] [-progressive] < arit.jpg > orig2.jpg ++ ++to verify correct operation. ++ ++Thus, you can easily verify the enhanced compression performance ++of the arithmetic coding version compared to the Huffman (with ++fixed or custom tables) version. ++ ++The claim to evaluate was that arithmetic coding gives an average ++5-10% compression improvement against Huffman. ++Early tests with this implementation support this claim, and you ++can perform tests with own material. ++ ++Here are some actual results: ++ ++% ./jpegtran -optimize < testorig.jpg > testopt.jpg ++% ./jpegtran -arithmetic < testorig.jpg > testarit.jpg ++% ./jpegtran < testarit.jpg > testorig2.jpg ++% ./jpegtran -arithmetic -progressive < testorig.jpg > testaritp.jpg ++% ./jpegtran < testaritp.jpg > testorig3.jpg ++% ./jpegtran -optimize < ../butterfly.jpg > ../buttopt.jpg ++% ./jpegtran -progressive < ../butterfly.jpg > ../buttprog.jpg ++% ./jpegtran -arithmetic < ../butterfly.jpg > ../buttarit.jpg ++% ./jpegtran < ../buttarit.jpg > ../butterfly2.jpg ++% ./jpegtran -arithmetic -progressive < ../butterfly.jpg > ../buttaritp.jpg ++% ./jpegtran < ../buttaritp.jpg > ../butterfly3.jpg ++% ls -l test*.jpg ++-rw-r--r-- 1 guivol 5153 Apr 13 18:51 testarit.jpg ++-rw-r--r-- 1 guivol 5186 Apr 13 18:51 testaritp.jpg ++-rw-r--r-- 1 guivol 5756 Apr 2 15:10 testimg.jpg ++-rw-r--r-- 1 guivol 5645 Apr 2 15:10 testimgp.jpg ++-rw-r--r-- 1 guivol 5463 Apr 13 18:51 testopt.jpg ++-rw-r--r-- 1 guivol 5770 Apr 2 15:10 testorig.jpg ++-rw-r--r-- 1 guivol 5770 Apr 13 18:51 testorig2.jpg ++-rw-r--r-- 1 guivol 5770 Apr 13 18:51 testorig3.jpg ++-rw-r--r-- 1 guivol 5655 Apr 2 15:10 testprog.jpg ++% ls -l ../butt*.jpg ++-rw-r--r-- 1 guivol 460091 Apr 13 18:52 ../buttarit.jpg ++-rw-r--r-- 1 guivol 453703 Apr 13 18:52 ../buttaritp.jpg ++-rw-r--r-- 1 guivol 527823 Nov 19 18:41 ../butterfly.jpg ++-rw-r--r-- 1 guivol 527823 Apr 13 18:52 ../butterfly2.jpg ++-rw-r--r-- 1 guivol 527823 Apr 13 18:52 ../butterfly3.jpg ++-rw-r--r-- 1 guivol 511834 Apr 13 18:52 ../buttopt.jpg ++-rw-r--r-- 1 guivol 492237 Apr 13 18:52 ../buttprog.jpg ++% ++ ++Note that arithmetic coding requires only a single processing ++pass due to its fully-adaptive nature, and compared to one-pass ++(fixed tables) Huffman the arithmetic coded version consistently ++achieves 10% compression improvement. ++Compared with two-pass (custom tables) Huffman the improvement ++is 5-10%. ++ ++Note that I wasn't able yet to cross-check interoperability of ++the produced files with other implementations. ++Thus, I can't be sure that the files are compliant to the spec, ++but I hope so and the tests support it. ++The encoding and decoding processes should be correct anyway, ++however, in the sense that they are complementary to each other ++and thus retain data integrity. ++ ++I would appreciate any indications for compliance or interoperability ++with other implementations from somebody. ++Please let me know if you are able to cross-check something. ++ ++ ++Installation ++============ ++ ++The installation is a 2-stage procedure: ++ ++1. Preparing the IJG package for potential incorporation ++ of the arithmetic coding feature. ++ ++2. Incorporation of the actual arithmetic coding modules ++ and enabling the feature for usage. ++ ++The reason for this 2-stage process is the hope to make ++step 1 obsolete in future IJG releases. ++The actual implementation should remain separate IMHO due ++to the different usage conditions. ++ ++Step 1: ++ ++1.1. Copy all files from the subdirectory 'patchv6b' into ++ the IJG software's v6b source directory. ++ This includes minor patches to some files and 3 extra ++ files which hold place for the actual implementation. ++ ++1.2. Update your Makefile/Projectfile for the inclusion of ++ the 3 extra files. This will be done automatically ++ if you use a configure-generated makefile and type ++ './configure' (reconfigure). ++ ++1.3. Recompile ('make'). ++ ++See the file 'PATCHES' in 'patchv6b' for details. ++ ++Step 2: ++ ++2.1. Replace the 3 placeholder files by the actual implementation ++ modules. ++ ++2.2. Enable application support of the new features by #defining ++ C_ARITH_CODING_SUPPORTED and D_ARITH_CODING_SUPPORTED ++ in 'jmorecfg.h'. ++ ++2.3. Recompile ('make'). ++ ++Note that I suggest to add 3 placeholder files to the IJG ++distribution. This would remove the need for system-dependent ++changes (Makefiles) and thus considerably simplify the actual ++installation for systems without a configure-generated makefile. ++ ++ ++References ++========== ++ ++- The Independent JPEG Group's software ++ ++- JBIG-KIT lossless image compression library by Markus Kuhn ++ ++- William B. Pennebaker, Joan L. Mitchell: ++ "JPEG Still Image Data Compression Standard", ++ Van Nostrand Reinhold, 1993, ISBN 0-442-01272-1. ++ ++- jpeg-faq (http://www.faqs.org/faqs/jpeg-faq/) ++ ++- compression-faq (http://www.faqs.org/faqs/compression-faq/) +diff --git a/jaricom.c b/jaricom.c +new file mode 100644 +index 0000000..e4292b0 +--- /dev/null ++++ b/jaricom.c +@@ -0,0 +1,149 @@ ++/* ++ * jaricom.c ++ * ++ * Copyright (C) 1997, Guido Vollbeding . ++ * This file is NOT part of the Independent JPEG Group's software ++ * for legal reasons. ++ * See the accompanying README file for conditions of distribution and use. ++ * ++ * This file contains probability estimation tables for common use in ++ * arithmetic entropy encoding and decoding routines. ++ * ++ * This data represents Table D.2 in the JPEG spec (ISO/IEC IS 10918-1 ++ * and CCITT Recommendation ITU-T T.81) and Table 24 in the JBIG spec ++ * (ISO/IEC IS 11544 and CCITT Recommendation ITU-T T.82). ++ */ ++ ++#define JPEG_INTERNALS ++#include "jinclude.h" ++#include "jpeglib.h" ++ ++/* The following #define specifies the packing of the four components ++ * into the compact INT32 representation. ++ * Note that this formula must match the actual arithmetic encoder ++ * and decoder implementation. The implementation has to be changed ++ * if this formula is changed. ++ * The current organisation is leaned on Markus Kuhn's JBIG ++ * implementation (jbig_tab.c). ++ */ ++ ++#define V(a,b,c,d) (((INT32)a << 16) | ((INT32)c << 8) | ((INT32)d << 7) | b) ++ ++const INT32 jaritab[113] = { ++/* ++ * Index, Qe_Value, Next_Index_LPS, Next_Index_MPS, Switch_MPS ++ */ ++/* 0 */ V( 0x5a1d, 1, 1, 1 ), ++/* 1 */ V( 0x2586, 14, 2, 0 ), ++/* 2 */ V( 0x1114, 16, 3, 0 ), ++/* 3 */ V( 0x080b, 18, 4, 0 ), ++/* 4 */ V( 0x03d8, 20, 5, 0 ), ++/* 5 */ V( 0x01da, 23, 6, 0 ), ++/* 6 */ V( 0x00e5, 25, 7, 0 ), ++/* 7 */ V( 0x006f, 28, 8, 0 ), ++/* 8 */ V( 0x0036, 30, 9, 0 ), ++/* 9 */ V( 0x001a, 33, 10, 0 ), ++/* 10 */ V( 0x000d, 35, 11, 0 ), ++/* 11 */ V( 0x0006, 9, 12, 0 ), ++/* 12 */ V( 0x0003, 10, 13, 0 ), ++/* 13 */ V( 0x0001, 12, 13, 0 ), ++/* 14 */ V( 0x5a7f, 15, 15, 1 ), ++/* 15 */ V( 0x3f25, 36, 16, 0 ), ++/* 16 */ V( 0x2cf2, 38, 17, 0 ), ++/* 17 */ V( 0x207c, 39, 18, 0 ), ++/* 18 */ V( 0x17b9, 40, 19, 0 ), ++/* 19 */ V( 0x1182, 42, 20, 0 ), ++/* 20 */ V( 0x0cef, 43, 21, 0 ), ++/* 21 */ V( 0x09a1, 45, 22, 0 ), ++/* 22 */ V( 0x072f, 46, 23, 0 ), ++/* 23 */ V( 0x055c, 48, 24, 0 ), ++/* 24 */ V( 0x0406, 49, 25, 0 ), ++/* 25 */ V( 0x0303, 51, 26, 0 ), ++/* 26 */ V( 0x0240, 52, 27, 0 ), ++/* 27 */ V( 0x01b1, 54, 28, 0 ), ++/* 28 */ V( 0x0144, 56, 29, 0 ), ++/* 29 */ V( 0x00f5, 57, 30, 0 ), ++/* 30 */ V( 0x00b7, 59, 31, 0 ), ++/* 31 */ V( 0x008a, 60, 32, 0 ), ++/* 32 */ V( 0x0068, 62, 33, 0 ), ++/* 33 */ V( 0x004e, 63, 34, 0 ), ++/* 34 */ V( 0x003b, 32, 35, 0 ), ++/* 35 */ V( 0x002c, 33, 9, 0 ), ++/* 36 */ V( 0x5ae1, 37, 37, 1 ), ++/* 37 */ V( 0x484c, 64, 38, 0 ), ++/* 38 */ V( 0x3a0d, 65, 39, 0 ), ++/* 39 */ V( 0x2ef1, 67, 40, 0 ), ++/* 40 */ V( 0x261f, 68, 41, 0 ), ++/* 41 */ V( 0x1f33, 69, 42, 0 ), ++/* 42 */ V( 0x19a8, 70, 43, 0 ), ++/* 43 */ V( 0x1518, 72, 44, 0 ), ++/* 44 */ V( 0x1177, 73, 45, 0 ), ++/* 45 */ V( 0x0e74, 74, 46, 0 ), ++/* 46 */ V( 0x0bfb, 75, 47, 0 ), ++/* 47 */ V( 0x09f8, 77, 48, 0 ), ++/* 48 */ V( 0x0861, 78, 49, 0 ), ++/* 49 */ V( 0x0706, 79, 50, 0 ), ++/* 50 */ V( 0x05cd, 48, 51, 0 ), ++/* 51 */ V( 0x04de, 50, 52, 0 ), ++/* 52 */ V( 0x040f, 50, 53, 0 ), ++/* 53 */ V( 0x0363, 51, 54, 0 ), ++/* 54 */ V( 0x02d4, 52, 55, 0 ), ++/* 55 */ V( 0x025c, 53, 56, 0 ), ++/* 56 */ V( 0x01f8, 54, 57, 0 ), ++/* 57 */ V( 0x01a4, 55, 58, 0 ), ++/* 58 */ V( 0x0160, 56, 59, 0 ), ++/* 59 */ V( 0x0125, 57, 60, 0 ), ++/* 60 */ V( 0x00f6, 58, 61, 0 ), ++/* 61 */ V( 0x00cb, 59, 62, 0 ), ++/* 62 */ V( 0x00ab, 61, 63, 0 ), ++/* 63 */ V( 0x008f, 61, 32, 0 ), ++/* 64 */ V( 0x5b12, 65, 65, 1 ), ++/* 65 */ V( 0x4d04, 80, 66, 0 ), ++/* 66 */ V( 0x412c, 81, 67, 0 ), ++/* 67 */ V( 0x37d8, 82, 68, 0 ), ++/* 68 */ V( 0x2fe8, 83, 69, 0 ), ++/* 69 */ V( 0x293c, 84, 70, 0 ), ++/* 70 */ V( 0x2379, 86, 71, 0 ), ++/* 71 */ V( 0x1edf, 87, 72, 0 ), ++/* 72 */ V( 0x1aa9, 87, 73, 0 ), ++/* 73 */ V( 0x174e, 72, 74, 0 ), ++/* 74 */ V( 0x1424, 72, 75, 0 ), ++/* 75 */ V( 0x119c, 74, 76, 0 ), ++/* 76 */ V( 0x0f6b, 74, 77, 0 ), ++/* 77 */ V( 0x0d51, 75, 78, 0 ), ++/* 78 */ V( 0x0bb6, 77, 79, 0 ), ++/* 79 */ V( 0x0a40, 77, 48, 0 ), ++/* 80 */ V( 0x5832, 80, 81, 1 ), ++/* 81 */ V( 0x4d1c, 88, 82, 0 ), ++/* 82 */ V( 0x438e, 89, 83, 0 ), ++/* 83 */ V( 0x3bdd, 90, 84, 0 ), ++/* 84 */ V( 0x34ee, 91, 85, 0 ), ++/* 85 */ V( 0x2eae, 92, 86, 0 ), ++/* 86 */ V( 0x299a, 93, 87, 0 ), ++/* 87 */ V( 0x2516, 86, 71, 0 ), ++/* 88 */ V( 0x5570, 88, 89, 1 ), ++/* 89 */ V( 0x4ca9, 95, 90, 0 ), ++/* 90 */ V( 0x44d9, 96, 91, 0 ), ++/* 91 */ V( 0x3e22, 97, 92, 0 ), ++/* 92 */ V( 0x3824, 99, 93, 0 ), ++/* 93 */ V( 0x32b4, 99, 94, 0 ), ++/* 94 */ V( 0x2e17, 93, 86, 0 ), ++/* 95 */ V( 0x56a8, 95, 96, 1 ), ++/* 96 */ V( 0x4f46, 101, 97, 0 ), ++/* 97 */ V( 0x47e5, 102, 98, 0 ), ++/* 98 */ V( 0x41cf, 103, 99, 0 ), ++/* 99 */ V( 0x3c3d, 104, 100, 0 ), ++/* 100 */ V( 0x375e, 99, 93, 0 ), ++/* 101 */ V( 0x5231, 105, 102, 0 ), ++/* 102 */ V( 0x4c0f, 106, 103, 0 ), ++/* 103 */ V( 0x4639, 107, 104, 0 ), ++/* 104 */ V( 0x415e, 103, 99, 0 ), ++/* 105 */ V( 0x5627, 105, 106, 1 ), ++/* 106 */ V( 0x50e7, 108, 107, 0 ), ++/* 107 */ V( 0x4b85, 109, 103, 0 ), ++/* 108 */ V( 0x5597, 110, 109, 0 ), ++/* 109 */ V( 0x504f, 111, 107, 0 ), ++/* 110 */ V( 0x5a10, 110, 111, 1 ), ++/* 111 */ V( 0x5522, 112, 109, 0 ), ++/* 112 */ V( 0x59eb, 112, 111, 1 ) ++}; +diff --git a/jdarith.c b/jdarith.c +new file mode 100644 +index 0000000..1ef513e +--- /dev/null ++++ b/jdarith.c +@@ -0,0 +1,762 @@ ++/* ++ * jdarith.c ++ * ++ * Copyright (C) 1997, Guido Vollbeding . ++ * This file is NOT part of the Independent JPEG Group's software ++ * for legal reasons. ++ * See the accompanying README file for conditions of distribution and use. ++ * ++ * This file contains portable arithmetic entropy decoding routines for JPEG ++ * (implementing the ISO/IEC IS 10918-1 and CCITT Recommendation ITU-T T.81). ++ * ++ * Both sequential and progressive modes are supported in this single module. ++ * ++ * Suspension is not currently supported in this module. ++ */ ++ ++#define JPEG_INTERNALS ++#include "jinclude.h" ++#include "jpeglib.h" ++ ++ ++/* Expanded entropy decoder object for arithmetic decoding. */ ++ ++typedef struct { ++ struct jpeg_entropy_decoder pub; /* public fields */ ++ ++ INT32 c; /* C register, base of coding interval + input bit buffer */ ++ INT32 a; /* A register, normalized size of coding interval */ ++ int ct; /* bit shift counter, # of bits left in bit buffer part of C */ ++ /* init: ct = -16 */ ++ /* run: ct = 0..7 */ ++ /* error: ct = -1 */ ++ int last_dc_val[MAX_COMPS_IN_SCAN]; /* last DC coef for each component */ ++ int dc_context[MAX_COMPS_IN_SCAN]; /* context index for DC conditioning */ ++ ++ unsigned int restarts_to_go; /* MCUs left in this restart interval */ ++ ++ /* Pointers to statistics areas (these workspaces have image lifespan) */ ++ unsigned char * dc_stats[NUM_ARITH_TBLS]; ++ unsigned char * ac_stats[NUM_ARITH_TBLS]; ++} arith_entropy_decoder; ++ ++typedef arith_entropy_decoder * arith_entropy_ptr; ++ ++/* The following two definitions specify the allocation chunk size ++ * for the statistics area. ++ * According to sections F.1.4.4.1.3 and F.1.4.4.2, we need at least ++ * 49 statistics bins for DC, and 245 statistics bins for AC coding. ++ * Note that we use one additional AC bin for codings with fixed ++ * probability (0.5), thus the minimum number for AC is 246. ++ * ++ * We use a compact representation with 1 byte per statistics bin, ++ * thus the numbers directly represent byte sizes. ++ * This 1 byte per statistics bin contains the meaning of the MPS ++ * (more probable symbol) in the highest bit (mask 0x80), and the ++ * index into the probability estimation state machine table ++ * in the lower bits (mask 0x7F). ++ */ ++ ++#define DC_STAT_BINS 64 ++#define AC_STAT_BINS 256 ++ ++ ++LOCAL(int) ++get_byte (j_decompress_ptr cinfo) ++/* Read next input byte; we do not support suspension in this module. */ ++{ ++ struct jpeg_source_mgr * src = cinfo->src; ++ ++ if (src->bytes_in_buffer == 0) ++ if (! (*src->fill_input_buffer) (cinfo)) ++ ERREXIT(cinfo, JERR_CANT_SUSPEND); ++ src->bytes_in_buffer--; ++ return GETJOCTET(*src->next_input_byte++); ++} ++ ++ ++/* ++ * The core arithmetic decoding routine (common in JPEG and JBIG). ++ * This needs to go as fast as possible. ++ * Machine-dependent optimization facilities ++ * are not utilized in this portable implementation. ++ * However, this code should be fairly efficient and ++ * may be a good base for further optimizations anyway. ++ * ++ * Return value is 0 or 1 (binary decision). ++ * ++ * Note: I've changed the handling of the code base & bit ++ * buffer register C compared to other implementations ++ * based on the standards layout & procedures. ++ * While it also contains both the actual base of the ++ * coding interval (16 bits) and the next-bits buffer, ++ * the cut-point between these two parts is floating ++ * (instead of fixed) with the bit shift counter CT. ++ * Thus, we also need only one (variable instead of ++ * fixed size) shift for the LPS/MPS decision, and ++ * we can get away with any renormalization update ++ * of C (except for new data insertion, of course). ++ * ++ * I've also introduced a new scheme for accessing ++ * the probability estimation state machine table, ++ * derived from Markus Kuhn's JBIG implementation. ++ */ ++ ++LOCAL(int) ++arith_decode (j_decompress_ptr cinfo, unsigned char *st) ++{ ++ extern const INT32 jaritab[]; ++ register arith_entropy_ptr e = (arith_entropy_ptr) cinfo->entropy; ++ register unsigned char nl, nm; ++ register INT32 qe, temp; ++ register int sv, data; ++ ++ /* Renormalization & data input per section D.2.6 */ ++ while (e->a < 0x8000L) { ++ if (--e->ct < 0) { ++ /* Need to fetch next data byte */ ++ if (cinfo->unread_marker) ++ data = 0; /* stuff zero data */ ++ else { ++ data = get_byte(cinfo); /* read next input byte */ ++ if (data == 0xFF) { /* zero stuff or marker code */ ++ do data = get_byte(cinfo); ++ while (data == 0xFF); /* swallow extra 0xFF bytes */ ++ if (data == 0) ++ data = 0xFF; /* discard stuffed zero byte */ ++ else { ++ /* Note: Different from the Huffman decoder, hitting ++ * a marker while processing the compressed data ++ * segment is legal in arithmetic coding. ++ * The convention is to supply zero data ++ * then until decoding is complete. ++ */ ++ cinfo->unread_marker = data; ++ data = 0; ++ } ++ } ++ } ++ e->c = (e->c << 8) | data; /* insert data into C register */ ++ if ((e->ct += 8) < 0) /* update bit shift counter */ ++ /* Need more initial bytes */ ++ if (++e->ct == 0) ++ /* Got 2 initial bytes -> re-init A and exit loop */ ++ e->a = 0x8000L; /* => e->a = 0x10000L after loop exit */ ++ } ++ e->a <<= 1; ++ } ++ ++ /* Fetch values from our compact representation of Table D.2: ++ * Qe values and probability estimation state machine ++ */ ++ sv = *st; ++ qe = jaritab[sv & 0x7F]; /* => Qe_Value */ ++ nl = qe & 0xFF; qe >>= 8; /* Next_Index_LPS + Switch_MPS */ ++ nm = qe & 0xFF; qe >>= 8; /* Next_Index_MPS */ ++ ++ /* Decode & estimation procedures per sections D.2.4 & D.2.5 */ ++ temp = e->a - qe; ++ e->a = temp; ++ temp <<= e->ct; ++ if (e->c >= temp) { ++ e->c -= temp; ++ /* Conditional LPS (less probable symbol) exchange */ ++ if (e->a < qe) { ++ e->a = qe; ++ *st = (sv & 0x80) ^ nm; /* Estimate_after_MPS */ ++ } else { ++ e->a = qe; ++ *st = (sv & 0x80) ^ nl; /* Estimate_after_LPS */ ++ sv ^= 0x80; /* Exchange LPS/MPS */ ++ } ++ } else if (e->a < 0x8000L) { ++ /* Conditional MPS (more probable symbol) exchange */ ++ if (e->a < qe) { ++ *st = (sv & 0x80) ^ nl; /* Estimate_after_LPS */ ++ sv ^= 0x80; /* Exchange LPS/MPS */ ++ } else { ++ *st = (sv & 0x80) ^ nm; /* Estimate_after_MPS */ ++ } ++ } ++ ++ return sv >> 7; ++} ++ ++ ++/* ++ * Check for a restart marker & resynchronize decoder. ++ */ ++ ++LOCAL(void) ++process_restart (j_decompress_ptr cinfo) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ int ci; ++ jpeg_component_info * compptr; ++ ++ /* Advance past the RSTn marker */ ++ if (! (*cinfo->marker->read_restart_marker) (cinfo)) ++ ERREXIT(cinfo, JERR_CANT_SUSPEND); ++ ++ for (ci = 0; ci < cinfo->comps_in_scan; ci++) { ++ compptr = cinfo->cur_comp_info[ci]; ++ /* Re-initialize statistics areas */ ++ if (cinfo->progressive_mode == 0 || (cinfo->Ss == 0 && cinfo->Ah == 0)) { ++ MEMZERO(entropy->dc_stats[compptr->dc_tbl_no], DC_STAT_BINS); ++ /* Reset DC predictions to 0 */ ++ entropy->last_dc_val[ci] = 0; ++ entropy->dc_context[ci] = 0; ++ } ++ if (cinfo->progressive_mode == 0 || cinfo->Ss) { ++ MEMZERO(entropy->ac_stats[compptr->ac_tbl_no], AC_STAT_BINS); ++ } ++ } ++ ++ /* Reset arithmetic decoding variables */ ++ entropy->c = 0; ++ entropy->a = 0; ++ entropy->ct = -16; /* force reading 2 initial bytes to fill C */ ++ ++ /* Reset restart counter */ ++ entropy->restarts_to_go = cinfo->restart_interval; ++} ++ ++ ++/* ++ * Arithmetic MCU decoding. ++ * Each of these routines decodes and returns one MCU's worth of ++ * arithmetic-compressed coefficients. ++ * The coefficients are reordered from zigzag order into natural array order, ++ * but are not dequantized. ++ * ++ * The i'th block of the MCU is stored into the block pointed to by ++ * MCU_data[i]. WE ASSUME THIS AREA IS INITIALLY ZEROED BY THE CALLER. ++ */ ++ ++/* ++ * MCU decoding for DC initial scan (either spectral selection, ++ * or first pass of successive approximation). ++ */ ++ ++METHODDEF(boolean) ++decode_mcu_DC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ JBLOCKROW block; ++ unsigned char *st; ++ int blkn, ci, tbl, sign; ++ int v, m; ++ ++ /* Process restart marker if needed */ ++ if (cinfo->restart_interval) { ++ if (entropy->restarts_to_go == 0) ++ process_restart(cinfo); ++ entropy->restarts_to_go--; ++ } ++ ++ if (entropy->ct == -1) return TRUE; /* if error do nothing */ ++ ++ /* Outer loop handles each block in the MCU */ ++ ++ for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) { ++ block = MCU_data[blkn]; ++ ci = cinfo->MCU_membership[blkn]; ++ tbl = cinfo->cur_comp_info[ci]->dc_tbl_no; ++ ++ /* Sections F.2.4.1 & F.1.4.4.1: Decoding of DC coefficients */ ++ ++ /* Table F.4: Point to statistics bin S0 for DC coefficient coding */ ++ st = entropy->dc_stats[tbl] + entropy->dc_context[ci]; ++ ++ /* Figure F.19: Decode_DC_DIFF */ ++ if (arith_decode(cinfo, st) == 0) ++ entropy->dc_context[ci] = 0; ++ else { ++ /* Figure F.21: Decoding nonzero value v */ ++ /* Figure F.22: Decoding the sign of v */ ++ sign = arith_decode(cinfo, st + 1); ++ st += 2; st += sign; ++ /* Figure F.23: Decoding the magnitude category of v */ ++ if ((m = arith_decode(cinfo, st)) != 0) { ++ st = entropy->dc_stats[tbl] + 20; /* Table F.4: X1 = 20 */ ++ while (arith_decode(cinfo, st)) { ++ if ((m <<= 1) == 0x8000) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* magnitude overflow */ ++ return TRUE; ++ } ++ st += 1; ++ } ++ } ++ /* Section F.1.4.4.1.2: Establish dc_context conditioning category */ ++ if (m < (int) (((INT32) 1 << cinfo->arith_dc_L[tbl]) >> 1)) ++ entropy->dc_context[ci] = 0; /* zero diff category */ ++ else if (m > (int) (((INT32) 1 << cinfo->arith_dc_U[tbl]) >> 1)) ++ entropy->dc_context[ci] = 12 + (sign * 4); /* large diff category */ ++ else ++ entropy->dc_context[ci] = 4 + (sign * 4); /* small diff category */ ++ v = m; ++ /* Figure F.24: Decoding the magnitude bit pattern of v */ ++ st += 14; ++ while (m >>= 1) ++ if (arith_decode(cinfo, st)) v |= m; ++ v += 1; if (sign) v = -v; ++ entropy->last_dc_val[ci] += v; ++ } ++ ++ /* Scale and output the DC coefficient (assumes jpeg_natural_order[0]=0) */ ++ (*block)[0] = (JCOEF) (entropy->last_dc_val[ci] << cinfo->Al); ++ } ++ ++ return TRUE; ++} ++ ++ ++/* ++ * MCU decoding for AC initial scan (either spectral selection, ++ * or first pass of successive approximation). ++ */ ++ ++METHODDEF(boolean) ++decode_mcu_AC_first (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ JBLOCKROW block; ++ unsigned char *st; ++ int tbl, sign, k; ++ int v, m; ++ ++ /* Process restart marker if needed */ ++ if (cinfo->restart_interval) { ++ if (entropy->restarts_to_go == 0) ++ process_restart(cinfo); ++ entropy->restarts_to_go--; ++ } ++ ++ if (entropy->ct == -1) return TRUE; /* if error do nothing */ ++ ++ /* There is always only one block per MCU */ ++ block = MCU_data[0]; ++ tbl = cinfo->cur_comp_info[0]->ac_tbl_no; ++ ++ /* Sections F.2.4.2 & F.1.4.4.2: Decoding of AC coefficients */ ++ ++ /* Figure F.20: Decode_AC_coefficients */ ++ for (k = cinfo->Ss; k <= cinfo->Se; k++) { ++ st = entropy->ac_stats[tbl] + 3 * (k - 1); ++ if (arith_decode(cinfo, st)) break; /* EOB flag */ ++ while (arith_decode(cinfo, st + 1) == 0) { ++ st += 3; k++; ++ if (k > cinfo->Se) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* spectral overflow */ ++ return TRUE; ++ } ++ } ++ /* Figure F.21: Decoding nonzero value v */ ++ /* Figure F.22: Decoding the sign of v */ ++ entropy->ac_stats[tbl][245] = 0; ++ sign = arith_decode(cinfo, entropy->ac_stats[tbl] + 245); ++ st += 2; ++ /* Figure F.23: Decoding the magnitude category of v */ ++ if ((m = arith_decode(cinfo, st)) != 0) { ++ if (arith_decode(cinfo, st)) { ++ m <<= 1; ++ st = entropy->ac_stats[tbl] + ++ (k <= cinfo->arith_ac_K[tbl] ? 189 : 217); ++ while (arith_decode(cinfo, st)) { ++ if ((m <<= 1) == 0x8000) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* magnitude overflow */ ++ return TRUE; ++ } ++ st += 1; ++ } ++ } ++ } ++ v = m; ++ /* Figure F.24: Decoding the magnitude bit pattern of v */ ++ st += 14; ++ while (m >>= 1) ++ if (arith_decode(cinfo, st)) v |= m; ++ v += 1; if (sign) v = -v; ++ /* Scale and output coefficient in natural (dezigzagged) order */ ++ (*block)[jpeg_natural_order[k]] = (JCOEF) (v << cinfo->Al); ++ } ++ ++ return TRUE; ++} ++ ++ ++/* ++ * MCU decoding for DC successive approximation refinement scan. ++ */ ++ ++METHODDEF(boolean) ++decode_mcu_DC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ unsigned char st[4]; ++ int p1, blkn; ++ ++ /* Process restart marker if needed */ ++ if (cinfo->restart_interval) { ++ if (entropy->restarts_to_go == 0) ++ process_restart(cinfo); ++ entropy->restarts_to_go--; ++ } ++ ++ p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */ ++ ++ /* Outer loop handles each block in the MCU */ ++ ++ for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) { ++ st[0] = 0; /* use fixed probability estimation */ ++ /* Encoded data is simply the next bit of the two's-complement DC value */ ++ if (arith_decode(cinfo, st)) ++ MCU_data[blkn][0][0] |= p1; ++ } ++ ++ return TRUE; ++} ++ ++ ++/* ++ * MCU decoding for AC successive approximation refinement scan. ++ */ ++ ++METHODDEF(boolean) ++decode_mcu_AC_refine (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ JBLOCKROW block; ++ JCOEFPTR thiscoef; ++ unsigned char *st; ++ int tbl, k, kex; ++ int p1, m1; ++ ++ /* Process restart marker if needed */ ++ if (cinfo->restart_interval) { ++ if (entropy->restarts_to_go == 0) ++ process_restart(cinfo); ++ entropy->restarts_to_go--; ++ } ++ ++ if (entropy->ct == -1) return TRUE; /* if error do nothing */ ++ ++ /* There is always only one block per MCU */ ++ block = MCU_data[0]; ++ tbl = cinfo->cur_comp_info[0]->ac_tbl_no; ++ ++ p1 = 1 << cinfo->Al; /* 1 in the bit position being coded */ ++ m1 = (-1) << cinfo->Al; /* -1 in the bit position being coded */ ++ ++ /* Establish EOBx (previous stage end-of-block) index */ ++ for (kex = cinfo->Se + 1; kex > 1; kex--) ++ if ((*block)[jpeg_natural_order[kex - 1]]) break; ++ ++ for (k = cinfo->Ss; k <= cinfo->Se; k++) { ++ st = entropy->ac_stats[tbl] + 3 * (k - 1); ++ if (k >= kex) ++ if (arith_decode(cinfo, st)) break; /* EOB flag */ ++ for (;;) { ++ thiscoef = *block + jpeg_natural_order[k]; ++ if (*thiscoef) { /* previously nonzero coef */ ++ if (arith_decode(cinfo, st + 2)) ++ if (*thiscoef < 0) ++ *thiscoef += m1; ++ else ++ *thiscoef += p1; ++ break; ++ } ++ if (arith_decode(cinfo, st + 1)) { /* newly nonzero coef */ ++ entropy->ac_stats[tbl][245] = 0; ++ if (arith_decode(cinfo, entropy->ac_stats[tbl] + 245)) ++ *thiscoef = m1; ++ else ++ *thiscoef = p1; ++ break; ++ } ++ st += 3; k++; ++ if (k > cinfo->Se) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* spectral overflow */ ++ return TRUE; ++ } ++ } ++ } ++ ++ return TRUE; ++} ++ ++ ++/* ++ * Decode one MCU's worth of arithmetic-compressed coefficients. ++ */ ++ ++METHODDEF(boolean) ++decode_mcu (j_decompress_ptr cinfo, JBLOCKROW *MCU_data) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ jpeg_component_info * compptr; ++ JBLOCKROW block; ++ unsigned char *st; ++ int blkn, ci, tbl, sign, k; ++ int v, m; ++ ++ /* Process restart marker if needed */ ++ if (cinfo->restart_interval) { ++ if (entropy->restarts_to_go == 0) ++ process_restart(cinfo); ++ entropy->restarts_to_go--; ++ } ++ ++ if (entropy->ct == -1) return TRUE; /* if error do nothing */ ++ ++ /* Outer loop handles each block in the MCU */ ++ ++ for (blkn = 0; blkn < cinfo->blocks_in_MCU; blkn++) { ++ block = MCU_data[blkn]; ++ ci = cinfo->MCU_membership[blkn]; ++ compptr = cinfo->cur_comp_info[ci]; ++ ++ /* Sections F.2.4.1 & F.1.4.4.1: Decoding of DC coefficients */ ++ ++ tbl = compptr->dc_tbl_no; ++ ++ /* Table F.4: Point to statistics bin S0 for DC coefficient coding */ ++ st = entropy->dc_stats[tbl] + entropy->dc_context[ci]; ++ ++ /* Figure F.19: Decode_DC_DIFF */ ++ if (arith_decode(cinfo, st) == 0) ++ entropy->dc_context[ci] = 0; ++ else { ++ /* Figure F.21: Decoding nonzero value v */ ++ /* Figure F.22: Decoding the sign of v */ ++ sign = arith_decode(cinfo, st + 1); ++ st += 2; st += sign; ++ /* Figure F.23: Decoding the magnitude category of v */ ++ if ((m = arith_decode(cinfo, st)) != 0) { ++ st = entropy->dc_stats[tbl] + 20; /* Table F.4: X1 = 20 */ ++ while (arith_decode(cinfo, st)) { ++ if ((m <<= 1) == 0x8000) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* magnitude overflow */ ++ return TRUE; ++ } ++ st += 1; ++ } ++ } ++ /* Section F.1.4.4.1.2: Establish dc_context conditioning category */ ++ if (m < (int) (((INT32) 1 << cinfo->arith_dc_L[tbl]) >> 1)) ++ entropy->dc_context[ci] = 0; /* zero diff category */ ++ else if (m > (int) (((INT32) 1 << cinfo->arith_dc_U[tbl]) >> 1)) ++ entropy->dc_context[ci] = 12 + (sign * 4); /* large diff category */ ++ else ++ entropy->dc_context[ci] = 4 + (sign * 4); /* small diff category */ ++ v = m; ++ /* Figure F.24: Decoding the magnitude bit pattern of v */ ++ st += 14; ++ while (m >>= 1) ++ if (arith_decode(cinfo, st)) v |= m; ++ v += 1; if (sign) v = -v; ++ entropy->last_dc_val[ci] += v; ++ } ++ ++ (*block)[0] = (JCOEF) entropy->last_dc_val[ci]; ++ ++ /* Sections F.2.4.2 & F.1.4.4.2: Decoding of AC coefficients */ ++ ++ tbl = compptr->ac_tbl_no; ++ ++ /* Figure F.20: Decode_AC_coefficients */ ++ for (k = 1; k < DCTSIZE2; k++) { ++ st = entropy->ac_stats[tbl] + 3 * (k - 1); ++ if (arith_decode(cinfo, st)) break; /* EOB flag */ ++ while (arith_decode(cinfo, st + 1) == 0) { ++ st += 3; k++; ++ if (k >= DCTSIZE2) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* spectral overflow */ ++ return TRUE; ++ } ++ } ++ /* Figure F.21: Decoding nonzero value v */ ++ /* Figure F.22: Decoding the sign of v */ ++ entropy->ac_stats[tbl][245] = 0; ++ sign = arith_decode(cinfo, entropy->ac_stats[tbl] + 245); ++ st += 2; ++ /* Figure F.23: Decoding the magnitude category of v */ ++ if ((m = arith_decode(cinfo, st)) != 0) { ++ if (arith_decode(cinfo, st)) { ++ m <<= 1; ++ st = entropy->ac_stats[tbl] + ++ (k <= cinfo->arith_ac_K[tbl] ? 189 : 217); ++ while (arith_decode(cinfo, st)) { ++ if ((m <<= 1) == 0x8000) { ++ WARNMS(cinfo, JWRN_ARITH_BAD_CODE); ++ entropy->ct = -1; /* magnitude overflow */ ++ return TRUE; ++ } ++ st += 1; ++ } ++ } ++ } ++ v = m; ++ /* Figure F.24: Decoding the magnitude bit pattern of v */ ++ st += 14; ++ while (m >>= 1) ++ if (arith_decode(cinfo, st)) v |= m; ++ v += 1; if (sign) v = -v; ++ (*block)[jpeg_natural_order[k]] = (JCOEF) v; ++ } ++ } ++ ++ return TRUE; ++} ++ ++ ++/* ++ * Initialize for an arithmetic-compressed scan. ++ */ ++ ++METHODDEF(void) ++start_pass (j_decompress_ptr cinfo) ++{ ++ arith_entropy_ptr entropy = (arith_entropy_ptr) cinfo->entropy; ++ int ci, tbl; ++ jpeg_component_info * compptr; ++ ++ if (cinfo->progressive_mode) { ++ /* Validate progressive scan parameters */ ++ if (cinfo->Ss == 0) { ++ if (cinfo->Se != 0) ++ goto bad; ++ } else { ++ /* need not check Ss/Se < 0 since they came from unsigned bytes */ ++ if (cinfo->Se < cinfo->Ss || cinfo->Se >= DCTSIZE2) ++ goto bad; ++ /* AC scans may have only one component */ ++ if (cinfo->comps_in_scan != 1) ++ goto bad; ++ } ++ if (cinfo->Ah != 0) { ++ /* Successive approximation refinement scan: must have Al = Ah-1. */ ++ if (cinfo->Ah-1 != cinfo->Al) ++ goto bad; ++ } ++ if (cinfo->Al > 13) { /* need not check for < 0 */ ++ bad: ++ ERREXIT4(cinfo, JERR_BAD_PROGRESSION, ++ cinfo->Ss, cinfo->Se, cinfo->Ah, cinfo->Al); ++ } ++ /* Update progression status, and verify that scan order is legal. ++ * Note that inter-scan inconsistencies are treated as warnings ++ * not fatal errors ... not clear if this is right way to behave. ++ */ ++ for (ci = 0; ci < cinfo->comps_in_scan; ci++) { ++ int coefi, cindex = cinfo->cur_comp_info[ci]->component_index; ++ int *coef_bit_ptr = & cinfo->coef_bits[cindex][0]; ++ if (cinfo->Ss && coef_bit_ptr[0] < 0) /* AC without prior DC scan */ ++ WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, 0); ++ for (coefi = cinfo->Ss; coefi <= cinfo->Se; coefi++) { ++ int expected = (coef_bit_ptr[coefi] < 0) ? 0 : coef_bit_ptr[coefi]; ++ if (cinfo->Ah != expected) ++ WARNMS2(cinfo, JWRN_BOGUS_PROGRESSION, cindex, coefi); ++ coef_bit_ptr[coefi] = cinfo->Al; ++ } ++ } ++ /* Select MCU decoding routine */ ++ if (cinfo->Ah == 0) { ++ if (cinfo->Ss == 0) ++ entropy->pub.decode_mcu = decode_mcu_DC_first; ++ else ++ entropy->pub.decode_mcu = decode_mcu_AC_first; ++ } else { ++ if (cinfo->Ss == 0) ++ entropy->pub.decode_mcu = decode_mcu_DC_refine; ++ else ++ entropy->pub.decode_mcu = decode_mcu_AC_refine; ++ } ++ } else { ++ /* Check that the scan parameters Ss, Se, Ah/Al are OK for sequential JPEG. ++ * This ought to be an error condition, but we make it a warning because ++ * there are some baseline files out there with all zeroes in these bytes. ++ */ ++ if (cinfo->Ss != 0 || cinfo->Se != DCTSIZE2-1 || ++ cinfo->Ah != 0 || cinfo->Al != 0) ++ WARNMS(cinfo, JWRN_NOT_SEQUENTIAL); ++ /* Select MCU decoding routine */ ++ entropy->pub.decode_mcu = decode_mcu; ++ } ++ ++ for (ci = 0; ci < cinfo->comps_in_scan; ci++) { ++ compptr = cinfo->cur_comp_info[ci]; ++ /* Allocate & initialize requested statistics areas */ ++ if (cinfo->progressive_mode == 0 || (cinfo->Ss == 0 && cinfo->Ah == 0)) { ++ tbl = compptr->dc_tbl_no; ++ if (tbl < 0 || tbl >= NUM_ARITH_TBLS) ++ ERREXIT1(cinfo, JERR_NO_ARITH_TABLE, tbl); ++ if (entropy->dc_stats[tbl] == NULL) ++ entropy->dc_stats[tbl] = (unsigned char *) (*cinfo->mem->alloc_small) ++ ((j_common_ptr) cinfo, JPOOL_IMAGE, DC_STAT_BINS); ++ MEMZERO(entropy->dc_stats[tbl], DC_STAT_BINS); ++ /* Initialize DC predictions to 0 */ ++ entropy->last_dc_val[ci] = 0; ++ entropy->dc_context[ci] = 0; ++ } ++ if (cinfo->progressive_mode == 0 || cinfo->Ss) { ++ tbl = compptr->ac_tbl_no; ++ if (tbl < 0 || tbl >= NUM_ARITH_TBLS) ++ ERREXIT1(cinfo, JERR_NO_ARITH_TABLE, tbl); ++ if (entropy->ac_stats[tbl] == NULL) ++ entropy->ac_stats[tbl] = (unsigned char *) (*cinfo->mem->alloc_small) ++ ((j_common_ptr) cinfo, JPOOL_IMAGE, AC_STAT_BINS); ++ MEMZERO(entropy->ac_stats[tbl], AC_STAT_BINS); ++ } ++ } ++ ++ /* Initialize arithmetic decoding variables */ ++ entropy->c = 0; ++ entropy->a = 0; ++ entropy->ct = -16; /* force reading 2 initial bytes to fill C */ ++ ++ /* Initialize restart counter */ ++ entropy->restarts_to_go = cinfo->restart_interval; ++} ++ ++ ++/* ++ * Module initialization routine for arithmetic entropy decoding. ++ */ ++ ++GLOBAL(void) ++jinit_arith_decoder (j_decompress_ptr cinfo) ++{ ++ arith_entropy_ptr entropy; ++ int i; ++ ++ entropy = (arith_entropy_ptr) ++ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, ++ SIZEOF(arith_entropy_decoder)); ++ cinfo->entropy = (struct jpeg_entropy_decoder *) entropy; ++ entropy->pub.start_pass = start_pass; ++ ++ /* Mark tables unallocated */ ++ for (i = 0; i < NUM_ARITH_TBLS; i++) { ++ entropy->dc_stats[i] = NULL; ++ entropy->ac_stats[i] = NULL; ++ } ++ ++ if (cinfo->progressive_mode) { ++ /* Create progression status table */ ++ int *coef_bit_ptr, ci; ++ cinfo->coef_bits = (int (*)[DCTSIZE2]) ++ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE, ++ cinfo->num_components*DCTSIZE2*SIZEOF(int)); ++ coef_bit_ptr = & cinfo->coef_bits[0][0]; ++ for (ci = 0; ci < cinfo->num_components; ci++) ++ for (i = 0; i < DCTSIZE2; i++) ++ *coef_bit_ptr++ = -1; ++ } ++} +diff --git a/jdmaster.c b/jdmaster.c +index 8314b67..537abc7 100644 +--- a/jdmaster.c ++++ b/jdmaster.c +@@ -384,7 +384,7 @@ master_selection (j_decompress_ptr cinfo) + jinit_inverse_dct(cinfo); + /* Entropy decoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { +- ERREXIT(cinfo, JERR_ARITH_NOTIMPL); ++ jinit_arith_decoder(cinfo); + } else { + if (cinfo->progressive_mode) { + #ifdef D_PROGRESSIVE_SUPPORTED +diff --git a/jdtrans.c b/jdtrans.c +index 6c0ab71..fcc9ae9 100644 +--- a/jdtrans.c ++++ b/jdtrans.c +@@ -101,7 +101,7 @@ transdecode_master_selection (j_decompress_ptr cinfo) + + /* Entropy decoding: either Huffman or arithmetic coding. */ + if (cinfo->arith_code) { +- ERREXIT(cinfo, JERR_ARITH_NOTIMPL); ++ jinit_arith_decoder(cinfo); + } else { + if (cinfo->progressive_mode) { + #ifdef D_PROGRESSIVE_SUPPORTED +diff --git a/jerror.h b/jerror.h +index fc2fffe..109e3d3 100644 +--- a/jerror.h ++++ b/jerror.h +@@ -93,6 +93,7 @@ JMESSAGE(JERR_MISSING_DATA, "Scan script does not transmit all data") + JMESSAGE(JERR_MODE_CHANGE, "Invalid color quantization mode change") + JMESSAGE(JERR_NOTIMPL, "Not implemented yet") + JMESSAGE(JERR_NOT_COMPILED, "Requested feature was omitted at compile time") ++JMESSAGE(JERR_NO_ARITH_TABLE, "Arithmetic table 0x%02x was not defined") + JMESSAGE(JERR_NO_BACKING_STORE, "Backing store not supported") + JMESSAGE(JERR_NO_HUFF_TABLE, "Huffman table 0x%02x was not defined") + JMESSAGE(JERR_NO_IMAGE, "JPEG datastream contains no image") +@@ -170,6 +171,7 @@ JMESSAGE(JTRC_UNKNOWN_IDS, + JMESSAGE(JTRC_XMS_CLOSE, "Freed XMS handle %u") + JMESSAGE(JTRC_XMS_OPEN, "Obtained XMS handle %u") + JMESSAGE(JWRN_ADOBE_XFORM, "Unknown Adobe color transform code %d") ++JMESSAGE(JWRN_ARITH_BAD_CODE, "Corrupt JPEG data: bad arithmetic code") + JMESSAGE(JWRN_BOGUS_PROGRESSION, + "Inconsistent progression sequence for component %d coefficient %d") + JMESSAGE(JWRN_EXTRANEOUS_DATA, +diff --git a/jmorecfg.h b/jmorecfg.h +index 0e7fb72..4d66335 100644 +--- a/jmorecfg.h ++++ b/jmorecfg.h +@@ -283,7 +283,7 @@ typedef int boolean; + + /* Decoder capability options: */ + +-#undef D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ ++#define D_ARITH_CODING_SUPPORTED /* Arithmetic coding back end? */ + #define D_MULTISCAN_FILES_SUPPORTED /* Multiple-scan JPEG files? */ + #define D_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ + #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ +diff --git a/jpegint.h b/jpegint.h +index 7a31f51..78bb1cf 100644 +--- a/jpegint.h ++++ b/jpegint.h +@@ -313,6 +313,7 @@ struct jpeg_color_quantizer { + #define jinit_marker_reader jIMReader + #define jinit_huff_decoder jIHDecoder + #define jinit_phuff_decoder jIPHDecoder ++#define jinit_arith_decoder jIADecoder + #define jinit_inverse_dct jIIDCT + #define jinit_upsampler jIUpsampler + #define jinit_color_deconverter jIDColor +@@ -358,6 +359,7 @@ EXTERN(void) jinit_input_controller JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_marker_reader JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_huff_decoder JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_phuff_decoder JPP((j_decompress_ptr cinfo)); ++EXTERN(void) jinit_arith_decoder JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_inverse_dct JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_upsampler JPP((j_decompress_ptr cinfo)); + EXTERN(void) jinit_color_deconverter JPP((j_decompress_ptr cinfo)); +-- +1.7.2.3 +