yading@10: /*
yading@10:  * huffyuv codec for libavcodec
yading@10:  *
yading@10:  * Copyright (c) 2002-2003 Michael Niedermayer <michaelni@gmx.at>
yading@10:  *
yading@10:  * see http://www.pcisys.net/~melanson/codecs/huffyuv.txt for a description of
yading@10:  * the algorithm used
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * huffyuv codec for libavcodec.
yading@10:  */
yading@10: 
yading@10: #include <stdint.h>
yading@10: 
yading@10: #include "libavutil/mem.h"
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "huffyuv.h"
yading@10: 
yading@10: int ff_huffyuv_generate_bits_table(uint32_t *dst, const uint8_t *len_table)
yading@10: {
yading@10:     int len, index;
yading@10:     uint32_t bits = 0;
yading@10: 
yading@10:     for (len = 32; len > 0; len--) {
yading@10:         for (index = 0; index < 256; index++) {
yading@10:             if (len_table[index] == len)
yading@10:                 dst[index] = bits++;
yading@10:         }
yading@10:         if (bits & 1) {
yading@10:             av_log(NULL, AV_LOG_ERROR, "Error generating huffman table\n");
yading@10:             return -1;
yading@10:         }
yading@10:         bits >>= 1;
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: av_cold int ff_huffyuv_alloc_temp(HYuvContext *s)
yading@10: {
yading@10:     int i;
yading@10: 
yading@10:     if (s->bitstream_bpp<24) {
yading@10:         for (i=0; i<3; i++) {
yading@10:             s->temp[i]= av_malloc(s->width + 16);
yading@10:             if (!s->temp[i])
yading@10:                 return AVERROR(ENOMEM);
yading@10:         }
yading@10:     } else {
yading@10:         s->temp[0]= av_mallocz(4*s->width + 16);
yading@10:         if (!s->temp[0])
yading@10:             return AVERROR(ENOMEM);
yading@10:     }
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: av_cold void ff_huffyuv_common_init(AVCodecContext *avctx)
yading@10: {
yading@10:     HYuvContext *s = avctx->priv_data;
yading@10: 
yading@10:     s->avctx = avctx;
yading@10:     s->flags = avctx->flags;
yading@10: 
yading@10:     ff_dsputil_init(&s->dsp, avctx);
yading@10: 
yading@10:     s->width = avctx->width;
yading@10:     s->height = avctx->height;
yading@10: 
yading@10:     av_assert1(s->width > 0 && s->height > 0);
yading@10: }
yading@10: 
yading@10: av_cold void ff_huffyuv_common_end(HYuvContext *s)
yading@10: {
yading@10:     int i;
yading@10: 
yading@10:     for(i = 0; i < 3; i++) {
yading@10:         av_freep(&s->temp[i]);
yading@10:     }
yading@10: }