diff options
| -rw-r--r-- | rdswitch.c | 52 |
1 files changed, 46 insertions, 6 deletions
@@ -2,6 +2,7 @@ * rdswitch.c * * Copyright (C) 1991-1996, Thomas G. Lane. + * Copyright (C) 2010, D. R. Commander. * This file is part of the Independent JPEG Group's software. * For conditions of distribution and use, see the accompanying README file. * @@ -71,7 +72,7 @@ read_text_integer (FILE * file, long * result, int * termchar) #if JPEG_LIB_VERSION < 70 -static int q_scale_factor = 100; +static int q_scale_factor[NUM_QUANT_TBLS] = {100, 100, 100, 100}; #endif GLOBAL(boolean) @@ -116,7 +117,8 @@ read_quant_tables (j_compress_ptr cinfo, char * filename, boolean force_baseline jpeg_add_quant_table(cinfo, tblno, table, cinfo->q_scale_factor[tblno], force_baseline); #else - jpeg_add_quant_table(cinfo, tblno, table, q_scale_factor, force_baseline); + jpeg_add_quant_table(cinfo, tblno, table, q_scale_factor[tblno], + force_baseline); #endif tblno++; } @@ -271,6 +273,44 @@ bogus: #endif /* C_MULTISCAN_FILES_SUPPORTED */ +#if JPEG_LIB_VERSION < 70 +/* These are the sample quantization tables given in JPEG spec section K.1. + * The spec says that the values given produce "good" quality, and + * when divided by 2, "very good" quality. + */ +static const unsigned int std_luminance_quant_tbl[DCTSIZE2] = { + 16, 11, 10, 16, 24, 40, 51, 61, + 12, 12, 14, 19, 26, 58, 60, 55, + 14, 13, 16, 24, 40, 57, 69, 56, + 14, 17, 22, 29, 51, 87, 80, 62, + 18, 22, 37, 56, 68, 109, 103, 77, + 24, 35, 55, 64, 81, 104, 113, 92, + 49, 64, 78, 87, 103, 121, 120, 101, + 72, 92, 95, 98, 112, 100, 103, 99 +}; +static const unsigned int std_chrominance_quant_tbl[DCTSIZE2] = { + 17, 18, 24, 47, 99, 99, 99, 99, + 18, 21, 26, 66, 99, 99, 99, 99, + 24, 26, 56, 99, 99, 99, 99, 99, + 47, 66, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99, + 99, 99, 99, 99, 99, 99, 99, 99 +}; + + +LOCAL(void) +jpeg_default_qtables (j_compress_ptr cinfo, boolean force_baseline) +{ + jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl, + q_scale_factor[0], force_baseline); + jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl, + q_scale_factor[1], force_baseline); +} +#endif + + GLOBAL(boolean) set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline) /* Process a quality-ratings parameter string, of the form @@ -292,6 +332,8 @@ set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline) /* Convert user 0-100 rating to percentage scaling */ #if JPEG_LIB_VERSION >= 70 cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val); +#else + q_scale_factor[tblno] = jpeg_quality_scaling(val); #endif while (*arg && *arg++ != ',') /* advance to next segment of arg string */ ; @@ -299,14 +341,12 @@ set_quality_ratings (j_compress_ptr cinfo, char *arg, boolean force_baseline) /* reached end of parameter, set remaining factors to last value */ #if JPEG_LIB_VERSION >= 70 cinfo->q_scale_factor[tblno] = jpeg_quality_scaling(val); +#else + q_scale_factor[tblno] = jpeg_quality_scaling(val); #endif } } -#if JPEG_LIB_VERSION >= 70 jpeg_default_qtables(cinfo, force_baseline); -#else - jpeg_set_quality(cinfo, val, force_baseline); -#endif return TRUE; } |