diff options
Diffstat (limited to 'jpeg/jmorecfg.h')
| -rw-r--r-- | jpeg/jmorecfg.h | 105 |
1 files changed, 90 insertions, 15 deletions
diff --git a/jpeg/jmorecfg.h b/jpeg/jmorecfg.h index 928d052c8..679d68bdc 100644 --- a/jpeg/jmorecfg.h +++ b/jpeg/jmorecfg.h @@ -2,7 +2,7 @@ * jmorecfg.h * * Copyright (C) 1991-1997, Thomas G. Lane. - * Modified 1997-2009 by Guido Vollbeding. + * Modified 1997-2013 by Guido Vollbeding. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * @@ -15,13 +15,22 @@ /* * Define BITS_IN_JSAMPLE as either * 8 for 8-bit sample values (the usual setting) + * 9 for 9-bit sample values + * 10 for 10-bit sample values + * 11 for 11-bit sample values * 12 for 12-bit sample values - * Only 8 and 12 are legal data precisions for lossy JPEG according to the - * JPEG standard, and the IJG code does not support anything else! - * We do not support run-time selection of data precision, sorry. + * Only 8, 9, 10, 11, and 12 bits sample data precision are supported for + * full-feature DCT processing. Further depths up to 16-bit may be added + * later for the lossless modes of operation. + * Run-time selection and conversion of data precision will be added later + * and are currently not supported, sorry. + * Exception: The transcoding part (jpegtran) supports all settings in a + * single instance, since it operates on the level of DCT coefficients and + * not sample values. The DCT coefficients are of the same type (16 bits) + * in all cases (see below). */ -#define BITS_IN_JSAMPLE 8 /* use 8 or 12 */ +#define BITS_IN_JSAMPLE 8 /* use 8, 9, 10, 11, or 12 */ /* @@ -77,6 +86,48 @@ typedef char JSAMPLE; #endif /* BITS_IN_JSAMPLE == 8 */ +#if BITS_IN_JSAMPLE == 9 +/* JSAMPLE should be the smallest type that will hold the values 0..511. + * On nearly all machines "short" will do nicely. + */ + +typedef short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#define MAXJSAMPLE 511 +#define CENTERJSAMPLE 256 + +#endif /* BITS_IN_JSAMPLE == 9 */ + + +#if BITS_IN_JSAMPLE == 10 +/* JSAMPLE should be the smallest type that will hold the values 0..1023. + * On nearly all machines "short" will do nicely. + */ + +typedef short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#define MAXJSAMPLE 1023 +#define CENTERJSAMPLE 512 + +#endif /* BITS_IN_JSAMPLE == 10 */ + + +#if BITS_IN_JSAMPLE == 11 +/* JSAMPLE should be the smallest type that will hold the values 0..2047. + * On nearly all machines "short" will do nicely. + */ + +typedef short JSAMPLE; +#define GETJSAMPLE(value) ((int) (value)) + +#define MAXJSAMPLE 2047 +#define CENTERJSAMPLE 1024 + +#endif /* BITS_IN_JSAMPLE == 11 */ + + #if BITS_IN_JSAMPLE == 12 /* JSAMPLE should be the smallest type that will hold the values 0..4095. * On nearly all machines "short" will do nicely. @@ -210,6 +261,26 @@ typedef unsigned int JDIMENSION; #endif +/* The noreturn type identifier is used to declare functions + * which cannot return. + * Compilers can thus create more optimized code and perform + * better checks for warnings and errors. + * Static analyzer tools can make improved inferences about + * execution paths and are prevented from giving false alerts. + * + * Unfortunately, the proposed specifications of corresponding + * extensions in the Dec 2011 ISO C standard revision (C11), + * GCC, MSVC, etc. are not viable. + * Thus we introduce a user defined type to declare noreturn + * functions at least for clarity. A proper compiler would + * have a suitable noreturn type to match in place of void. + */ + +#ifndef HAVE_NORETURN_T +typedef void noreturn_t; +#endif + + /* Here is the pseudo-keyword for declaring pointers that must be "far" * on 80x86 machines. Most of the specialized coding for 80x86 is handled * by just saying "FAR *" where such a pointer is needed. In a few places @@ -233,14 +304,19 @@ typedef unsigned int JDIMENSION; */ #ifndef HAVE_BOOLEAN +#if defined FALSE || defined TRUE || defined QGLOBAL_H +/* Qt3 defines FALSE and TRUE as "const" variables in qglobal.h */ typedef int boolean; -#endif #ifndef FALSE /* in case these macros already exist */ #define FALSE 0 /* values of boolean */ #endif #ifndef TRUE #define TRUE 1 #endif +#else +typedef enum { FALSE = 0, TRUE = 1 } boolean; +#endif +#endif /* @@ -278,11 +354,12 @@ typedef int boolean; #define C_PROGRESSIVE_SUPPORTED /* Progressive JPEG? (Requires MULTISCAN)*/ #define DCT_SCALING_SUPPORTED /* Input rescaling via DCT? (Requires DCT_ISLOW)*/ #define ENTROPY_OPT_SUPPORTED /* Optimization of entropy coding parms? */ -/* Note: if you selected 12-bit data precision, it is dangerous to turn off - * ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only good for 8-bit - * precision, so jchuff.c normally uses entropy optimization to compute - * usable tables for higher precision. If you don't want to do optimization, - * you'll have to supply different default Huffman tables. +/* Note: if you selected more than 8-bit data precision, it is dangerous to + * turn off ENTROPY_OPT_SUPPORTED. The standard Huffman tables are only + * good for 8-bit precision, so arithmetic coding is recommended for higher + * precision. The Huffman encoder normally uses entropy optimization to + * compute usable tables for higher precision. Otherwise, you'll have to + * supply different default Huffman tables. * The exact same statements apply for progressive JPEG: the default tables * don't work for progressive mode. (This may get fixed, however.) */ @@ -293,7 +370,7 @@ typedef int boolean; #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 IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? */ +#define IDCT_SCALING_SUPPORTED /* Output rescaling via IDCT? (Requires DCT_ISLOW)*/ #define SAVE_MARKERS_SUPPORTED /* jpeg_save_markers() needed? */ #define BLOCK_SMOOTHING_SUPPORTED /* Block smoothing? (Progressive only) */ #undef UPSAMPLE_SCALING_SUPPORTED /* Output rescaling at upsample stage? */ @@ -312,9 +389,7 @@ typedef int boolean; * the offsets will also change the order in which colormap data is organized. * RESTRICTIONS: * 1. The sample applications cjpeg,djpeg do NOT support modified RGB formats. - * 2. These macros only affect RGB<=>YCbCr color conversion, so they are not - * useful if you are using JPEG color spaces other than YCbCr or grayscale. - * 3. The color quantizer modules will not behave desirably if RGB_PIXELSIZE + * 2. The color quantizer modules will not behave desirably if RGB_PIXELSIZE * is not 3 (they don't understand about dummy color components!). So you * can't use color quantization if you change that value. */ |