The problem with url_exist() is that it tries to open a resource in RDONLY mode. If the file is a FIFO and there is already a reading client, the open() call will hang. By using avio_check() with access mode of 0, the second reading process will check if the file exists without attempting to open it, thus avoiding the lock. Fix issue #1663. Signed-off-by: Anton Khirnov <anton@khirnov.net>
		
			
				
	
	
		
			471 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			471 lines
		
	
	
		
			14 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Image format
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 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
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 * Copyright (c) 2004 Michael Niedermayer
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 *
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 * This file is part of Libav.
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 *
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 * Libav 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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 * Libav 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 Libav; 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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#include "libavutil/intreadwrite.h"
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#include "libavutil/avstring.h"
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#include "avformat.h"
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#include "avio_internal.h"
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#include "internal.h"
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#include <strings.h>
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typedef struct {
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    int img_first;
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    int img_last;
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    int img_number;
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    int img_count;
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    int is_pipe;
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    char path[1024];
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} VideoData;
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typedef struct {
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    enum CodecID id;
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    const char *str;
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} IdStrMap;
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static const IdStrMap img_tags[] = {
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    { CODEC_ID_MJPEG     , "jpeg"},
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    { CODEC_ID_MJPEG     , "jpg"},
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    { CODEC_ID_LJPEG     , "ljpg"},
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    { CODEC_ID_PNG       , "png"},
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    { CODEC_ID_PNG       , "mng"},
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    { CODEC_ID_PPM       , "ppm"},
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    { CODEC_ID_PPM       , "pnm"},
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    { CODEC_ID_PGM       , "pgm"},
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    { CODEC_ID_PGMYUV    , "pgmyuv"},
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    { CODEC_ID_PBM       , "pbm"},
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    { CODEC_ID_PAM       , "pam"},
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    { CODEC_ID_MPEG1VIDEO, "mpg1-img"},
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    { CODEC_ID_MPEG2VIDEO, "mpg2-img"},
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    { CODEC_ID_MPEG4     , "mpg4-img"},
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    { CODEC_ID_FFV1      , "ffv1-img"},
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    { CODEC_ID_RAWVIDEO  , "y"},
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    { CODEC_ID_BMP       , "bmp"},
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    { CODEC_ID_GIF       , "gif"},
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    { CODEC_ID_TARGA     , "tga"},
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    { CODEC_ID_TIFF      , "tiff"},
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    { CODEC_ID_TIFF      , "tif"},
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    { CODEC_ID_SGI       , "sgi"},
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    { CODEC_ID_PTX       , "ptx"},
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    { CODEC_ID_PCX       , "pcx"},
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    { CODEC_ID_SUNRAST   , "sun"},
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    { CODEC_ID_SUNRAST   , "ras"},
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    { CODEC_ID_SUNRAST   , "rs"},
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    { CODEC_ID_SUNRAST   , "im1"},
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    { CODEC_ID_SUNRAST   , "im8"},
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    { CODEC_ID_SUNRAST   , "im24"},
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    { CODEC_ID_SUNRAST   , "sunras"},
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    { CODEC_ID_JPEG2000  , "jp2"},
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    { CODEC_ID_DPX       , "dpx"},
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    { CODEC_ID_PICTOR    , "pic"},
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    { CODEC_ID_NONE      , NULL}
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};
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static const int sizes[][2] = {
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    { 640, 480 },
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    { 720, 480 },
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    { 720, 576 },
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    { 352, 288 },
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    { 352, 240 },
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    { 160, 128 },
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    { 512, 384 },
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    { 640, 352 },
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    { 640, 240 },
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};
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static int infer_size(int *width_ptr, int *height_ptr, int size)
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{
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    int i;
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    for(i=0;i<FF_ARRAY_ELEMS(sizes);i++) {
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        if ((sizes[i][0] * sizes[i][1]) == size) {
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            *width_ptr = sizes[i][0];
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            *height_ptr = sizes[i][1];
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            return 0;
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        }
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    }
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    return -1;
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}
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static enum CodecID av_str2id(const IdStrMap *tags, const char *str)
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{
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    str= strrchr(str, '.');
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    if(!str) return CODEC_ID_NONE;
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    str++;
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    while (tags->id) {
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        if (!strcasecmp(str, tags->str))
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            return tags->id;
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        tags++;
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    }
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    return CODEC_ID_NONE;
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}
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/* return -1 if no image found */
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static int find_image_range(int *pfirst_index, int *plast_index,
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                            const char *path)
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{
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    char buf[1024];
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    int range, last_index, range1, first_index;
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    /* find the first image */
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    for(first_index = 0; first_index < 5; first_index++) {
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        if (av_get_frame_filename(buf, sizeof(buf), path, first_index) < 0){
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            *pfirst_index =
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            *plast_index = 1;
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            if (avio_check(buf, AVIO_FLAG_READ) > 0)
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                return 0;
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            return -1;
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        }
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        if (avio_check(buf, AVIO_FLAG_READ) > 0)
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            break;
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    }
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    if (first_index == 5)
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        goto fail;
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    /* find the last image */
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    last_index = first_index;
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    for(;;) {
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        range = 0;
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        for(;;) {
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            if (!range)
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                range1 = 1;
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            else
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                range1 = 2 * range;
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            if (av_get_frame_filename(buf, sizeof(buf), path,
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                                      last_index + range1) < 0)
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                goto fail;
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            if (avio_check(buf, AVIO_FLAG_READ) <= 0)
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                break;
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            range = range1;
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            /* just in case... */
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            if (range >= (1 << 30))
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                goto fail;
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        }
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        /* we are sure than image last_index + range exists */
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        if (!range)
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            break;
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        last_index += range;
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    }
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    *pfirst_index = first_index;
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    *plast_index = last_index;
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    return 0;
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 fail:
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    return -1;
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}
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static int read_probe(AVProbeData *p)
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{
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    if (p->filename && av_str2id(img_tags, p->filename)) {
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        if (av_filename_number_test(p->filename))
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            return AVPROBE_SCORE_MAX;
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        else
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            return AVPROBE_SCORE_MAX/2;
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    }
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    return 0;
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}
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enum CodecID ff_guess_image2_codec(const char *filename)
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{
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    return av_str2id(img_tags, filename);
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}
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#if FF_API_GUESS_IMG2_CODEC
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enum CodecID av_guess_image2_codec(const char *filename){
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    return av_str2id(img_tags, filename);
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}
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#endif
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static int read_header(AVFormatContext *s1, AVFormatParameters *ap)
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{
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    VideoData *s = s1->priv_data;
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    int first_index, last_index;
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    AVStream *st;
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    s1->ctx_flags |= AVFMTCTX_NOHEADER;
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    st = av_new_stream(s1, 0);
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    if (!st) {
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        return AVERROR(ENOMEM);
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    }
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    av_strlcpy(s->path, s1->filename, sizeof(s->path));
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    s->img_number = 0;
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    s->img_count = 0;
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    /* find format */
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    if (s1->iformat->flags & AVFMT_NOFILE)
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        s->is_pipe = 0;
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    else{
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        s->is_pipe = 1;
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        st->need_parsing = AVSTREAM_PARSE_FULL;
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    }
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    if (!ap->time_base.num) {
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        av_set_pts_info(st, 60, 1, 25);
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    } else {
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        av_set_pts_info(st, 60, ap->time_base.num, ap->time_base.den);
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    }
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    if(ap->width && ap->height){
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        st->codec->width = ap->width;
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        st->codec->height= ap->height;
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    }
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    if (!s->is_pipe) {
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        if (find_image_range(&first_index, &last_index, s->path) < 0)
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            return AVERROR(ENOENT);
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        s->img_first = first_index;
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        s->img_last = last_index;
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        s->img_number = first_index;
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        /* compute duration */
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        st->start_time = 0;
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        st->duration = last_index - first_index + 1;
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    }
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    if(s1->video_codec_id){
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        st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
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        st->codec->codec_id = s1->video_codec_id;
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    }else if(s1->audio_codec_id){
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        st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
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        st->codec->codec_id = s1->audio_codec_id;
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    }else{
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        st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
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        st->codec->codec_id = av_str2id(img_tags, s->path);
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    }
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    if(st->codec->codec_type == AVMEDIA_TYPE_VIDEO && ap->pix_fmt != PIX_FMT_NONE)
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        st->codec->pix_fmt = ap->pix_fmt;
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    return 0;
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}
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static int read_packet(AVFormatContext *s1, AVPacket *pkt)
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{
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    VideoData *s = s1->priv_data;
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    char filename[1024];
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    int i;
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    int size[3]={0}, ret[3]={0};
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    AVIOContext *f[3];
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    AVCodecContext *codec= s1->streams[0]->codec;
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    if (!s->is_pipe) {
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        /* loop over input */
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        if (s1->loop_input && s->img_number > s->img_last) {
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            s->img_number = s->img_first;
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        }
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        if (s->img_number > s->img_last)
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            return AVERROR_EOF;
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        if (av_get_frame_filename(filename, sizeof(filename),
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                                  s->path, s->img_number)<0 && s->img_number > 1)
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            return AVERROR(EIO);
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        for(i=0; i<3; i++){
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            if (avio_open(&f[i], filename, AVIO_FLAG_READ) < 0) {
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                if(i==1)
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                    break;
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                av_log(s1, AV_LOG_ERROR, "Could not open file : %s\n",filename);
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                return AVERROR(EIO);
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            }
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            size[i]= avio_size(f[i]);
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            if(codec->codec_id != CODEC_ID_RAWVIDEO)
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                break;
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            filename[ strlen(filename) - 1 ]= 'U' + i;
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        }
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        if(codec->codec_id == CODEC_ID_RAWVIDEO && !codec->width)
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            infer_size(&codec->width, &codec->height, size[0]);
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    } else {
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        f[0] = s1->pb;
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        if (f[0]->eof_reached)
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            return AVERROR(EIO);
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        size[0]= 4096;
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    }
 | 
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 | 
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    av_new_packet(pkt, size[0] + size[1] + size[2]);
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    pkt->stream_index = 0;
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    pkt->flags |= AV_PKT_FLAG_KEY;
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 | 
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    pkt->size= 0;
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    for(i=0; i<3; i++){
 | 
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        if(size[i]){
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            ret[i]= avio_read(f[i], pkt->data + pkt->size, size[i]);
 | 
						|
            if (!s->is_pipe)
 | 
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                avio_close(f[i]);
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            if(ret[i]>0)
 | 
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                pkt->size += ret[i];
 | 
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        }
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    }
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 | 
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    if (ret[0] <= 0 || ret[1]<0 || ret[2]<0) {
 | 
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        av_free_packet(pkt);
 | 
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        return AVERROR(EIO); /* signal EOF */
 | 
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    } else {
 | 
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        s->img_count++;
 | 
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        s->img_number++;
 | 
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        return 0;
 | 
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    }
 | 
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}
 | 
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 | 
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#if CONFIG_IMAGE2_MUXER || CONFIG_IMAGE2PIPE_MUXER
 | 
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/******************************************************/
 | 
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/* image output */
 | 
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 | 
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static int write_header(AVFormatContext *s)
 | 
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{
 | 
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    VideoData *img = s->priv_data;
 | 
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 | 
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    img->img_number = 1;
 | 
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    av_strlcpy(img->path, s->filename, sizeof(img->path));
 | 
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 | 
						|
    /* find format */
 | 
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    if (s->oformat->flags & AVFMT_NOFILE)
 | 
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        img->is_pipe = 0;
 | 
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    else
 | 
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        img->is_pipe = 1;
 | 
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 | 
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    return 0;
 | 
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}
 | 
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 | 
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static int write_packet(AVFormatContext *s, AVPacket *pkt)
 | 
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{
 | 
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    VideoData *img = s->priv_data;
 | 
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    AVIOContext *pb[3];
 | 
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    char filename[1024];
 | 
						|
    AVCodecContext *codec= s->streams[ pkt->stream_index ]->codec;
 | 
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    int i;
 | 
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 | 
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    if (!img->is_pipe) {
 | 
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        if (av_get_frame_filename(filename, sizeof(filename),
 | 
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                                  img->path, img->img_number) < 0 && img->img_number>1) {
 | 
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            av_log(s, AV_LOG_ERROR,
 | 
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                   "Could not get frame filename number %d from pattern '%s'\n",
 | 
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                   img->img_number, img->path);
 | 
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            return AVERROR(EIO);
 | 
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        }
 | 
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        for(i=0; i<3; i++){
 | 
						|
            if (avio_open(&pb[i], filename, AVIO_FLAG_WRITE) < 0) {
 | 
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                av_log(s, AV_LOG_ERROR, "Could not open file : %s\n",filename);
 | 
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                return AVERROR(EIO);
 | 
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            }
 | 
						|
 | 
						|
            if(codec->codec_id != CODEC_ID_RAWVIDEO)
 | 
						|
                break;
 | 
						|
            filename[ strlen(filename) - 1 ]= 'U' + i;
 | 
						|
        }
 | 
						|
    } else {
 | 
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        pb[0] = s->pb;
 | 
						|
    }
 | 
						|
 | 
						|
    if(codec->codec_id == CODEC_ID_RAWVIDEO){
 | 
						|
        int ysize = codec->width * codec->height;
 | 
						|
        avio_write(pb[0], pkt->data        , ysize);
 | 
						|
        avio_write(pb[1], pkt->data + ysize, (pkt->size - ysize)/2);
 | 
						|
        avio_write(pb[2], pkt->data + ysize +(pkt->size - ysize)/2, (pkt->size - ysize)/2);
 | 
						|
        avio_flush(pb[1]);
 | 
						|
        avio_flush(pb[2]);
 | 
						|
        avio_close(pb[1]);
 | 
						|
        avio_close(pb[2]);
 | 
						|
    }else{
 | 
						|
        if(av_str2id(img_tags, s->filename) == CODEC_ID_JPEG2000){
 | 
						|
            AVStream *st = s->streams[0];
 | 
						|
            if(st->codec->extradata_size > 8 &&
 | 
						|
               AV_RL32(st->codec->extradata+4) == MKTAG('j','p','2','h')){
 | 
						|
                if(pkt->size < 8 || AV_RL32(pkt->data+4) != MKTAG('j','p','2','c'))
 | 
						|
                    goto error;
 | 
						|
                avio_wb32(pb[0], 12);
 | 
						|
                ffio_wfourcc(pb[0], "jP  ");
 | 
						|
                avio_wb32(pb[0], 0x0D0A870A); // signature
 | 
						|
                avio_wb32(pb[0], 20);
 | 
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                ffio_wfourcc(pb[0], "ftyp");
 | 
						|
                ffio_wfourcc(pb[0], "jp2 ");
 | 
						|
                avio_wb32(pb[0], 0);
 | 
						|
                ffio_wfourcc(pb[0], "jp2 ");
 | 
						|
                avio_write(pb[0], st->codec->extradata, st->codec->extradata_size);
 | 
						|
            }else if(pkt->size < 8 ||
 | 
						|
                     (!st->codec->extradata_size &&
 | 
						|
                      AV_RL32(pkt->data+4) != MKTAG('j','P',' ',' '))){ // signature
 | 
						|
            error:
 | 
						|
                av_log(s, AV_LOG_ERROR, "malformated jpeg2000 codestream\n");
 | 
						|
                return -1;
 | 
						|
            }
 | 
						|
        }
 | 
						|
        avio_write(pb[0], pkt->data, pkt->size);
 | 
						|
    }
 | 
						|
    avio_flush(pb[0]);
 | 
						|
    if (!img->is_pipe) {
 | 
						|
        avio_close(pb[0]);
 | 
						|
    }
 | 
						|
 | 
						|
    img->img_number++;
 | 
						|
    return 0;
 | 
						|
}
 | 
						|
 | 
						|
#endif /* CONFIG_IMAGE2_MUXER || CONFIG_IMAGE2PIPE_MUXER */
 | 
						|
 | 
						|
/* input */
 | 
						|
#if CONFIG_IMAGE2_DEMUXER
 | 
						|
AVInputFormat ff_image2_demuxer = {
 | 
						|
    .name           = "image2",
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("image2 sequence"),
 | 
						|
    .priv_data_size = sizeof(VideoData),
 | 
						|
    .read_probe     = read_probe,
 | 
						|
    .read_header    = read_header,
 | 
						|
    .read_packet    = read_packet,
 | 
						|
    .flags          = AVFMT_NOFILE,
 | 
						|
};
 | 
						|
#endif
 | 
						|
#if CONFIG_IMAGE2PIPE_DEMUXER
 | 
						|
AVInputFormat ff_image2pipe_demuxer = {
 | 
						|
    .name           = "image2pipe",
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("piped image2 sequence"),
 | 
						|
    .priv_data_size = sizeof(VideoData),
 | 
						|
    .read_header    = read_header,
 | 
						|
    .read_packet    = read_packet,
 | 
						|
};
 | 
						|
#endif
 | 
						|
 | 
						|
/* output */
 | 
						|
#if CONFIG_IMAGE2_MUXER
 | 
						|
AVOutputFormat ff_image2_muxer = {
 | 
						|
    .name           = "image2",
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("image2 sequence"),
 | 
						|
    .extensions     = "bmp,jpeg,jpg,ljpg,pam,pbm,pcx,pgm,pgmyuv,png,"
 | 
						|
                      "ppm,sgi,tga,tif,tiff,jp2",
 | 
						|
    .priv_data_size = sizeof(VideoData),
 | 
						|
    .video_codec    = CODEC_ID_MJPEG,
 | 
						|
    .write_header   = write_header,
 | 
						|
    .write_packet   = write_packet,
 | 
						|
    .flags          = AVFMT_NOTIMESTAMPS | AVFMT_NODIMENSIONS | AVFMT_NOFILE
 | 
						|
};
 | 
						|
#endif
 | 
						|
#if CONFIG_IMAGE2PIPE_MUXER
 | 
						|
AVOutputFormat ff_image2pipe_muxer = {
 | 
						|
    .name           = "image2pipe",
 | 
						|
    .long_name      = NULL_IF_CONFIG_SMALL("piped image2 sequence"),
 | 
						|
    .priv_data_size = sizeof(VideoData),
 | 
						|
    .video_codec    = CODEC_ID_MJPEG,
 | 
						|
    .write_header   = write_header,
 | 
						|
    .write_packet   = write_packet,
 | 
						|
    .flags          = AVFMT_NOTIMESTAMPS | AVFMT_NODIMENSIONS
 | 
						|
};
 | 
						|
#endif
 |