diff options
Diffstat (limited to 'src/3rdparty/libjpeg/jcmarker.c')
| -rw-r--r-- | src/3rdparty/libjpeg/jcmarker.c | 36 |
1 files changed, 19 insertions, 17 deletions
diff --git a/src/3rdparty/libjpeg/jcmarker.c b/src/3rdparty/libjpeg/jcmarker.c index 2e28983424..606c19af39 100644 --- a/src/3rdparty/libjpeg/jcmarker.c +++ b/src/3rdparty/libjpeg/jcmarker.c @@ -2,7 +2,7 @@ * jcmarker.c * * Copyright (C) 1991-1998, Thomas G. Lane. - * Modified 2003-2009 by Guido Vollbeding. + * Modified 2003-2010 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. * @@ -231,10 +231,10 @@ emit_dac (j_compress_ptr cinfo) char ac_in_use[NUM_ARITH_TBLS]; int length, i; jpeg_component_info *compptr; - + for (i = 0; i < NUM_ARITH_TBLS; i++) dc_in_use[i] = ac_in_use[i] = 0; - + for (i = 0; i < cinfo->comps_in_scan; i++) { compptr = cinfo->cur_comp_info[i]; /* DC needs no table for refinement scan */ @@ -244,23 +244,25 @@ emit_dac (j_compress_ptr cinfo) if (cinfo->Se) ac_in_use[compptr->ac_tbl_no] = 1; } - + length = 0; for (i = 0; i < NUM_ARITH_TBLS; i++) length += dc_in_use[i] + ac_in_use[i]; - - emit_marker(cinfo, M_DAC); - - emit_2bytes(cinfo, length*2 + 2); - - for (i = 0; i < NUM_ARITH_TBLS; i++) { - if (dc_in_use[i]) { - emit_byte(cinfo, i); - emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4)); - } - if (ac_in_use[i]) { - emit_byte(cinfo, i + 0x10); - emit_byte(cinfo, cinfo->arith_ac_K[i]); + + if (length) { + emit_marker(cinfo, M_DAC); + + emit_2bytes(cinfo, length*2 + 2); + + for (i = 0; i < NUM_ARITH_TBLS; i++) { + if (dc_in_use[i]) { + emit_byte(cinfo, i); + emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4)); + } + if (ac_in_use[i]) { + emit_byte(cinfo, i + 0x10); + emit_byte(cinfo, cinfo->arith_ac_K[i]); + } } } #endif /* C_ARITH_CODING_SUPPORTED */ |