95 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			95 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * huffyuv codec for libavcodec
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|  *
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|  * Copyright (c) 2002-2014 Michael Niedermayer <michaelni@gmx.at>
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|  *
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|  * see http://www.pcisys.net/~melanson/codecs/huffyuv.txt for a description of
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|  * the algorithm used
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| /**
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|  * @file
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|  * huffyuv codec for libavcodec.
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|  */
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| 
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| #include <stdint.h>
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| 
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| #include "libavutil/mem.h"
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| 
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| #include "avcodec.h"
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| #include "bswapdsp.h"
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| #include "huffyuv.h"
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| 
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| int ff_huffyuv_generate_bits_table(uint32_t *dst, const uint8_t *len_table, int n)
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| {
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|     int len, index;
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|     uint32_t bits = 0;
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| 
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|     for (len = 32; len > 0; len--) {
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|         for (index = 0; index < n; index++) {
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|             if (len_table[index] == len)
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|                 dst[index] = bits++;
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|         }
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|         if (bits & 1) {
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|             av_log(NULL, AV_LOG_ERROR, "Error generating huffman table\n");
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|             return -1;
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|         }
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|         bits >>= 1;
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|     }
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|     return 0;
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| }
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| 
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| av_cold int ff_huffyuv_alloc_temp(HYuvContext *s)
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| {
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|     int i;
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| 
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|     for (i=0; i<3; i++) {
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|         s->temp[i]= av_malloc(4*s->width + 16);
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|         if (!s->temp[i])
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|             return AVERROR(ENOMEM);
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|         s->temp16[i] = (uint16_t*)s->temp[i];
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|     }
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|     return 0;
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| }
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| 
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| av_cold void ff_huffyuv_common_init(AVCodecContext *avctx)
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| {
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|     HYuvContext *s = avctx->priv_data;
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| 
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|     s->avctx = avctx;
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|     s->flags = avctx->flags;
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| 
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|     ff_bswapdsp_init(&s->bdsp);
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| 
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|     s->width = avctx->width;
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|     s->height = avctx->height;
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| 
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|     av_assert1(s->width > 0 && s->height > 0);
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| }
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| 
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| av_cold void ff_huffyuv_common_end(HYuvContext *s)
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| {
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|     int i;
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| 
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|     for(i = 0; i < 3; i++) {
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|         av_freep(&s->temp[i]);
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|         s->temp16[i] = NULL;
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|     }
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| }
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