139 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			139 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * XBM image format
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|  *
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|  * Copyright (c) 2012 Paul B Mahol
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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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| #include "avcodec.h"
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| #include "internal.h"
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| #include "mathops.h"
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| 
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| static av_cold int xbm_decode_init(AVCodecContext *avctx)
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| {
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|     avctx->coded_frame = avcodec_alloc_frame();
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|     if (!avctx->coded_frame)
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|         return AVERROR(ENOMEM);
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| 
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|     return 0;
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| }
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| 
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| static int convert(uint8_t x)
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| {
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|     if (x >= 'a')
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|         x -= 87;
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|     else if (x >= 'A')
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|         x -= 55;
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|     else
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|         x -= '0';
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|     return x;
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| }
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| 
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| static int xbm_decode_frame(AVCodecContext *avctx, void *data,
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|                             int *got_frame, AVPacket *avpkt)
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| {
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|     AVFrame *p = avctx->coded_frame;
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|     const uint8_t *end, *ptr = avpkt->data;
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|     uint8_t *dst;
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|     int ret, linesize, i, j;
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| 
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|     end = avpkt->data + avpkt->size;
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|     while (!avctx->width || !avctx->height) {
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|         char name[256];
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|         int number, len;
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| 
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|         ptr += strcspn(ptr, "#");
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|         if (sscanf(ptr, "#define %256s %u", name, &number) != 2) {
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|             av_log(avctx, AV_LOG_ERROR, "Unexpected preprocessor directive\n");
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|             return AVERROR_INVALIDDATA;
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|         }
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| 
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|         len = strlen(name);
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|         if ((len > 6) && !avctx->height && !memcmp(name + len - 7, "_height", 7)) {
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|                 avctx->height = number;
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|         } else if ((len > 5) && !avctx->width && !memcmp(name + len - 6, "_width", 6)) {
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|                 avctx->width = number;
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|         } else {
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|             av_log(avctx, AV_LOG_ERROR, "Unknown define '%s'\n", name);
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|             return AVERROR_INVALIDDATA;
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|         }
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|         ptr += strcspn(ptr, "\n\r") + 1;
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|     }
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| 
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|     avctx->pix_fmt = AV_PIX_FMT_MONOWHITE;
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| 
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|     if (p->data[0])
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|         avctx->release_buffer(avctx, p);
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| 
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|     p->reference = 0;
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|     if ((ret = ff_get_buffer(avctx, p)) < 0)
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|         return ret;
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| 
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|     // goto start of image data
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|     ptr += strcspn(ptr, "{") + 1;
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| 
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|     linesize = (avctx->width + 7) / 8;
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|     for (i = 0; i < avctx->height; i++) {
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|         dst = p->data[0] + i * p->linesize[0];
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|         for (j = 0; j < linesize; j++) {
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|             uint8_t val;
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| 
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|             ptr += strcspn(ptr, "x") + 1;
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|             if (ptr < end && isxdigit(*ptr)) {
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|                 val = convert(*ptr);
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|                 ptr++;
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|                 if (isxdigit(*ptr))
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|                     val = (val << 4) + convert(*ptr);
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|                 *dst++ = ff_reverse[val];
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|             } else {
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|                 av_log(avctx, AV_LOG_ERROR, "Unexpected data at '%.8s'\n", ptr);
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|                 return AVERROR_INVALIDDATA;
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|             }
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|         }
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|     }
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| 
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|     p->key_frame = 1;
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|     p->pict_type = AV_PICTURE_TYPE_I;
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| 
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|     *got_frame       = 1;
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|     *(AVFrame *)data = *p;
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| 
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|     return avpkt->size;
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| }
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| 
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| static av_cold int xbm_decode_close(AVCodecContext *avctx)
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| {
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|     if (avctx->coded_frame->data[0])
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|         avctx->release_buffer(avctx, avctx->coded_frame);
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| 
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|     av_freep(&avctx->coded_frame);
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| 
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|     return 0;
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| }
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| 
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| AVCodec ff_xbm_decoder = {
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|     .name         = "xbm",
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|     .type         = AVMEDIA_TYPE_VIDEO,
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|     .id           = AV_CODEC_ID_XBM,
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|     .init         = xbm_decode_init,
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|     .close        = xbm_decode_close,
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|     .decode       = xbm_decode_frame,
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|     .capabilities = CODEC_CAP_DR1,
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|     .long_name    = NULL_IF_CONFIG_SMALL("XBM (X BitMap) image"),
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| };
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