mirror of
				https://github.com/nyanmisaka/ffmpeg-rockchip.git
				synced 2025-10-31 12:36:41 +08:00 
			
		
		
		
	
		
			
				
	
	
		
			529 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			529 lines
		
	
	
		
			17 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * GXF demuxer.
 | |
|  * Copyright (c) 2006 Reimar Doeffinger
 | |
|  *
 | |
|  * This file is part of FFmpeg.
 | |
|  *
 | |
|  * FFmpeg is free software; you can redistribute it and/or
 | |
|  * modify it under the terms of the GNU Lesser General Public
 | |
|  * License as published by the Free Software Foundation; either
 | |
|  * version 2.1 of the License, or (at your option) any later version.
 | |
|  *
 | |
|  * FFmpeg is distributed in the hope that it will be useful,
 | |
|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 | |
|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 | |
|  * Lesser General Public License for more details.
 | |
|  *
 | |
|  * You should have received a copy of the GNU Lesser General Public
 | |
|  * License along with FFmpeg; if not, write to the Free Software
 | |
|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 | |
|  */
 | |
| 
 | |
| #include "libavutil/common.h"
 | |
| #include "avformat.h"
 | |
| #include "internal.h"
 | |
| #include "gxf.h"
 | |
| 
 | |
| struct gxf_stream_info {
 | |
|     int64_t first_field;
 | |
|     int64_t last_field;
 | |
|     AVRational frames_per_second;
 | |
|     int32_t fields_per_frame;
 | |
| };
 | |
| 
 | |
| /**
 | |
|  * \brief parses a packet header, extracting type and length
 | |
|  * \param pb ByteIOContext to read header from
 | |
|  * \param type detected packet type is stored here
 | |
|  * \param length detected packet length, excluding header is stored here
 | |
|  * \return 0 if header not found or contains invalid data, 1 otherwise
 | |
|  */
 | |
| static int parse_packet_header(ByteIOContext *pb, GXFPktType *type, int *length) {
 | |
|     if (get_be32(pb))
 | |
|         return 0;
 | |
|     if (get_byte(pb) != 1)
 | |
|         return 0;
 | |
|     *type = get_byte(pb);
 | |
|     *length = get_be32(pb);
 | |
|     if ((*length >> 24) || *length < 16)
 | |
|         return 0;
 | |
|     *length -= 16;
 | |
|     if (get_be32(pb))
 | |
|         return 0;
 | |
|     if (get_byte(pb) != 0xe1)
 | |
|         return 0;
 | |
|     if (get_byte(pb) != 0xe2)
 | |
|         return 0;
 | |
|     return 1;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief check if file starts with a PKT_MAP header
 | |
|  */
 | |
| static int gxf_probe(AVProbeData *p) {
 | |
|     static const uint8_t startcode[] = {0, 0, 0, 0, 1, 0xbc}; // start with map packet
 | |
|     static const uint8_t endcode[] = {0, 0, 0, 0, 0xe1, 0xe2};
 | |
|     if (!memcmp(p->buf, startcode, sizeof(startcode)) &&
 | |
|         !memcmp(&p->buf[16 - sizeof(endcode)], endcode, sizeof(endcode)))
 | |
|         return AVPROBE_SCORE_MAX;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief gets the stream index for the track with the specified id, creates new
 | |
|  *        stream if not found
 | |
|  * \param id     id of stream to find / add
 | |
|  * \param format stream format identifier
 | |
|  */
 | |
| static int get_sindex(AVFormatContext *s, int id, int format) {
 | |
|     int i;
 | |
|     AVStream *st = NULL;
 | |
|     i = ff_find_stream_index(s, id);
 | |
|     if (i >= 0)
 | |
|         return i;
 | |
|     st = av_new_stream(s, id);
 | |
|     if (!st)
 | |
|         return AVERROR(ENOMEM);
 | |
|     switch (format) {
 | |
|         case 3:
 | |
|         case 4:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 | |
|             st->codec->codec_id = CODEC_ID_MJPEG;
 | |
|             break;
 | |
|         case 13:
 | |
|         case 15:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 | |
|             st->codec->codec_id = CODEC_ID_DVVIDEO;
 | |
|             break;
 | |
|         case 14:
 | |
|         case 16:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 | |
|             st->codec->codec_id = CODEC_ID_DVVIDEO;
 | |
|             break;
 | |
|         case 11:
 | |
|         case 12:
 | |
|         case 20:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 | |
|             st->codec->codec_id = CODEC_ID_MPEG2VIDEO;
 | |
|             st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
 | |
|             break;
 | |
|         case 22:
 | |
|         case 23:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
 | |
|             st->codec->codec_id = CODEC_ID_MPEG1VIDEO;
 | |
|             st->need_parsing = AVSTREAM_PARSE_HEADERS; //get keyframe flag etc.
 | |
|             break;
 | |
|         case 9:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 | |
|             st->codec->codec_id = CODEC_ID_PCM_S24LE;
 | |
|             st->codec->channels = 1;
 | |
|             st->codec->sample_rate = 48000;
 | |
|             st->codec->bit_rate = 3 * 1 * 48000 * 8;
 | |
|             st->codec->block_align = 3 * 1;
 | |
|             st->codec->bits_per_coded_sample = 24;
 | |
|             break;
 | |
|         case 10:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 | |
|             st->codec->codec_id = CODEC_ID_PCM_S16LE;
 | |
|             st->codec->channels = 1;
 | |
|             st->codec->sample_rate = 48000;
 | |
|             st->codec->bit_rate = 2 * 1 * 48000 * 8;
 | |
|             st->codec->block_align = 2 * 1;
 | |
|             st->codec->bits_per_coded_sample = 16;
 | |
|             break;
 | |
|         case 17:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
 | |
|             st->codec->codec_id = CODEC_ID_AC3;
 | |
|             st->codec->channels = 2;
 | |
|             st->codec->sample_rate = 48000;
 | |
|             break;
 | |
|         // timecode tracks:
 | |
|         case 7:
 | |
|         case 8:
 | |
|         case 24:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_DATA;
 | |
|             st->codec->codec_id = CODEC_ID_NONE;
 | |
|             break;
 | |
|         default:
 | |
|             st->codec->codec_type = AVMEDIA_TYPE_UNKNOWN;
 | |
|             st->codec->codec_id = CODEC_ID_NONE;
 | |
|             break;
 | |
|     }
 | |
|     return s->nb_streams - 1;
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief filters out interesting tags from material information.
 | |
|  * \param len length of tag section, will be adjusted to contain remaining bytes
 | |
|  * \param si struct to store collected information into
 | |
|  */
 | |
| static void gxf_material_tags(ByteIOContext *pb, int *len, struct gxf_stream_info *si) {
 | |
|     si->first_field = AV_NOPTS_VALUE;
 | |
|     si->last_field = AV_NOPTS_VALUE;
 | |
|     while (*len >= 2) {
 | |
|         GXFMatTag tag = get_byte(pb);
 | |
|         int tlen = get_byte(pb);
 | |
|         *len -= 2;
 | |
|         if (tlen > *len)
 | |
|             return;
 | |
|         *len -= tlen;
 | |
|         if (tlen == 4) {
 | |
|             uint32_t value = get_be32(pb);
 | |
|             if (tag == MAT_FIRST_FIELD)
 | |
|                 si->first_field = value;
 | |
|             else if (tag == MAT_LAST_FIELD)
 | |
|                 si->last_field = value;
 | |
|         } else
 | |
|             url_fskip(pb, tlen);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief convert fps tag value to AVRational fps
 | |
|  * \param fps fps value from tag
 | |
|  * \return fps as AVRational, or 0 / 0 if unknown
 | |
|  */
 | |
| static AVRational fps_tag2avr(int32_t fps) {
 | |
|     extern const AVRational ff_frame_rate_tab[];
 | |
|     if (fps < 1 || fps > 9) fps = 9;
 | |
|     return ff_frame_rate_tab[9 - fps]; // values have opposite order
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief convert UMF attributes flags to AVRational fps
 | |
|  * \param flags UMF flags to convert
 | |
|  * \return fps as AVRational, or 0 / 0 if unknown
 | |
|  */
 | |
| static AVRational fps_umf2avr(uint32_t flags) {
 | |
|     static const AVRational map[] = {{50, 1}, {60000, 1001}, {24, 1},
 | |
|         {25, 1}, {30000, 1001}};
 | |
|     int idx =  av_log2((flags & 0x7c0) >> 6);
 | |
|     return map[idx];
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief filters out interesting tags from track information.
 | |
|  * \param len length of tag section, will be adjusted to contain remaining bytes
 | |
|  * \param si struct to store collected information into
 | |
|  */
 | |
| static void gxf_track_tags(ByteIOContext *pb, int *len, struct gxf_stream_info *si) {
 | |
|     si->frames_per_second = (AVRational){0, 0};
 | |
|     si->fields_per_frame = 0;
 | |
|     while (*len >= 2) {
 | |
|         GXFTrackTag tag = get_byte(pb);
 | |
|         int tlen = get_byte(pb);
 | |
|         *len -= 2;
 | |
|         if (tlen > *len)
 | |
|             return;
 | |
|         *len -= tlen;
 | |
|         if (tlen == 4) {
 | |
|             uint32_t value = get_be32(pb);
 | |
|             if (tag == TRACK_FPS)
 | |
|                 si->frames_per_second = fps_tag2avr(value);
 | |
|             else if (tag == TRACK_FPF && (value == 1 || value == 2))
 | |
|                 si->fields_per_frame = value;
 | |
|         } else
 | |
|             url_fskip(pb, tlen);
 | |
|     }
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * \brief read index from FLT packet into stream 0 av_index
 | |
|  */
 | |
| static void gxf_read_index(AVFormatContext *s, int pkt_len) {
 | |
|     ByteIOContext *pb = s->pb;
 | |
|     AVStream *st = s->streams[0];
 | |
|     uint32_t fields_per_map = get_le32(pb);
 | |
|     uint32_t map_cnt = get_le32(pb);
 | |
|     int i;
 | |
|     pkt_len -= 8;
 | |
|     if (s->flags & AVFMT_FLAG_IGNIDX) {
 | |
|         url_fskip(pb, pkt_len);
 | |
|         return;
 | |
|     }
 | |
|     if (map_cnt > 1000) {
 | |
|         av_log(s, AV_LOG_ERROR, "too many index entries %u (%x)\n", map_cnt, map_cnt);
 | |
|         map_cnt = 1000;
 | |
|     }
 | |
|     if (pkt_len < 4 * map_cnt) {
 | |
|         av_log(s, AV_LOG_ERROR, "invalid index length\n");
 | |
|         url_fskip(pb, pkt_len);
 | |
|         return;
 | |
|     }
 | |
|     pkt_len -= 4 * map_cnt;
 | |
|     av_add_index_entry(st, 0, 0, 0, 0, 0);
 | |
|     for (i = 0; i < map_cnt; i++)
 | |
|         av_add_index_entry(st, (uint64_t)get_le32(pb) * 1024,
 | |
|                            i * (uint64_t)fields_per_map + 1, 0, 0, 0);
 | |
|     url_fskip(pb, pkt_len);
 | |
| }
 | |
| 
 | |
| static int gxf_header(AVFormatContext *s, AVFormatParameters *ap) {
 | |
|     ByteIOContext *pb = s->pb;
 | |
|     GXFPktType pkt_type;
 | |
|     int map_len;
 | |
|     int len;
 | |
|     AVRational main_timebase = {0, 0};
 | |
|     struct gxf_stream_info si;
 | |
|     int i;
 | |
|     if (!parse_packet_header(pb, &pkt_type, &map_len) || pkt_type != PKT_MAP) {
 | |
|         av_log(s, AV_LOG_ERROR, "map packet not found\n");
 | |
|         return 0;
 | |
|     }
 | |
|     map_len -= 2;
 | |
|     if (get_byte(pb) != 0x0e0 || get_byte(pb) != 0xff) {
 | |
|         av_log(s, AV_LOG_ERROR, "unknown version or invalid map preamble\n");
 | |
|         return 0;
 | |
|     }
 | |
|     map_len -= 2;
 | |
|     len = get_be16(pb); // length of material data section
 | |
|     if (len > map_len) {
 | |
|         av_log(s, AV_LOG_ERROR, "material data longer than map data\n");
 | |
|         return 0;
 | |
|     }
 | |
|     map_len -= len;
 | |
|     gxf_material_tags(pb, &len, &si);
 | |
|     url_fskip(pb, len);
 | |
|     map_len -= 2;
 | |
|     len = get_be16(pb); // length of track description
 | |
|     if (len > map_len) {
 | |
|         av_log(s, AV_LOG_ERROR, "track description longer than map data\n");
 | |
|         return 0;
 | |
|     }
 | |
|     map_len -= len;
 | |
|     while (len > 0) {
 | |
|         int track_type, track_id, track_len;
 | |
|         AVStream *st;
 | |
|         int idx;
 | |
|         len -= 4;
 | |
|         track_type = get_byte(pb);
 | |
|         track_id = get_byte(pb);
 | |
|         track_len = get_be16(pb);
 | |
|         len -= track_len;
 | |
|         gxf_track_tags(pb, &track_len, &si);
 | |
|         url_fskip(pb, track_len);
 | |
|         if (!(track_type & 0x80)) {
 | |
|            av_log(s, AV_LOG_ERROR, "invalid track type %x\n", track_type);
 | |
|            continue;
 | |
|         }
 | |
|         track_type &= 0x7f;
 | |
|         if ((track_id & 0xc0) != 0xc0) {
 | |
|            av_log(s, AV_LOG_ERROR, "invalid track id %x\n", track_id);
 | |
|            continue;
 | |
|         }
 | |
|         track_id &= 0x3f;
 | |
|         idx = get_sindex(s, track_id, track_type);
 | |
|         if (idx < 0) continue;
 | |
|         st = s->streams[idx];
 | |
|         if (!main_timebase.num || !main_timebase.den) {
 | |
|             main_timebase.num = si.frames_per_second.den;
 | |
|             main_timebase.den = si.frames_per_second.num * 2;
 | |
|         }
 | |
|         st->start_time = si.first_field;
 | |
|         if (si.first_field != AV_NOPTS_VALUE && si.last_field != AV_NOPTS_VALUE)
 | |
|             st->duration = si.last_field - si.first_field;
 | |
|     }
 | |
|     if (len < 0)
 | |
|         av_log(s, AV_LOG_ERROR, "invalid track description length specified\n");
 | |
|     if (map_len)
 | |
|         url_fskip(pb, map_len);
 | |
|     if (!parse_packet_header(pb, &pkt_type, &len)) {
 | |
|         av_log(s, AV_LOG_ERROR, "sync lost in header\n");
 | |
|         return -1;
 | |
|     }
 | |
|     if (pkt_type == PKT_FLT) {
 | |
|         gxf_read_index(s, len);
 | |
|         if (!parse_packet_header(pb, &pkt_type, &len)) {
 | |
|             av_log(s, AV_LOG_ERROR, "sync lost in header\n");
 | |
|             return -1;
 | |
|         }
 | |
|     }
 | |
|     if (pkt_type == PKT_UMF) {
 | |
|         if (len >= 0x39) {
 | |
|             AVRational fps;
 | |
|             len -= 0x39;
 | |
|             url_fskip(pb, 5); // preamble
 | |
|             url_fskip(pb, 0x30); // payload description
 | |
|             fps = fps_umf2avr(get_le32(pb));
 | |
|             if (!main_timebase.num || !main_timebase.den) {
 | |
|                 // this may not always be correct, but simply the best we can get
 | |
|                 main_timebase.num = fps.den;
 | |
|                 main_timebase.den = fps.num * 2;
 | |
|             }
 | |
|         } else
 | |
|             av_log(s, AV_LOG_INFO, "UMF packet too short\n");
 | |
|     } else
 | |
|         av_log(s, AV_LOG_INFO, "UMF packet missing\n");
 | |
|     url_fskip(pb, len);
 | |
|     // set a fallback value, 60000/1001 is specified for audio-only files
 | |
|     // so use that regardless of why we do not know the video frame rate.
 | |
|     if (!main_timebase.num || !main_timebase.den)
 | |
|         main_timebase = (AVRational){1001, 60000};
 | |
|     for (i = 0; i < s->nb_streams; i++) {
 | |
|         AVStream *st = s->streams[i];
 | |
|         av_set_pts_info(st, 32, main_timebase.num, main_timebase.den);
 | |
|     }
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| #define READ_ONE() \
 | |
|     { \
 | |
|         if (!max_interval-- || url_feof(pb)) \
 | |
|             goto out; \
 | |
|         tmp = tmp << 8 | get_byte(pb); \
 | |
|     }
 | |
| 
 | |
| /**
 | |
|  * \brief resync the stream on the next media packet with specified properties
 | |
|  * \param max_interval how many bytes to search for matching packet at most
 | |
|  * \param track track id the media packet must belong to, -1 for any
 | |
|  * \param timestamp minimum timestamp (== field number) the packet must have, -1 for any
 | |
|  * \return timestamp of packet found
 | |
|  */
 | |
| static int64_t gxf_resync_media(AVFormatContext *s, uint64_t max_interval, int track, int timestamp) {
 | |
|     uint32_t tmp;
 | |
|     uint64_t last_pos;
 | |
|     uint64_t last_found_pos = 0;
 | |
|     int cur_track;
 | |
|     int64_t cur_timestamp = AV_NOPTS_VALUE;
 | |
|     int len;
 | |
|     ByteIOContext *pb = s->pb;
 | |
|     GXFPktType type;
 | |
|     tmp = get_be32(pb);
 | |
| start:
 | |
|     while (tmp)
 | |
|         READ_ONE();
 | |
|     READ_ONE();
 | |
|     if (tmp != 1)
 | |
|         goto start;
 | |
|     last_pos = url_ftell(pb);
 | |
|     if (url_fseek(pb, -5, SEEK_CUR) < 0)
 | |
|         goto out;
 | |
|     if (!parse_packet_header(pb, &type, &len) || type != PKT_MEDIA) {
 | |
|         if (url_fseek(pb, last_pos, SEEK_SET) < 0)
 | |
|             goto out;
 | |
|         goto start;
 | |
|     }
 | |
|     get_byte(pb);
 | |
|     cur_track = get_byte(pb);
 | |
|     cur_timestamp = get_be32(pb);
 | |
|     last_found_pos = url_ftell(pb) - 16 - 6;
 | |
|     if ((track >= 0 && track != cur_track) || (timestamp >= 0 && timestamp > cur_timestamp)) {
 | |
|         if (url_fseek(pb, last_pos, SEEK_SET) >= 0)
 | |
|             goto start;
 | |
|     }
 | |
| out:
 | |
|     if (last_found_pos)
 | |
|         url_fseek(pb, last_found_pos, SEEK_SET);
 | |
|     return cur_timestamp;
 | |
| }
 | |
| 
 | |
| static int gxf_packet(AVFormatContext *s, AVPacket *pkt) {
 | |
|     ByteIOContext *pb = s->pb;
 | |
|     GXFPktType pkt_type;
 | |
|     int pkt_len;
 | |
|     while (!url_feof(pb)) {
 | |
|         AVStream *st;
 | |
|         int track_type, track_id, ret;
 | |
|         int field_nr, field_info, skip = 0;
 | |
|         int stream_index;
 | |
|         if (!parse_packet_header(pb, &pkt_type, &pkt_len)) {
 | |
|             if (!url_feof(pb))
 | |
|                 av_log(s, AV_LOG_ERROR, "sync lost\n");
 | |
|             return -1;
 | |
|         }
 | |
|         if (pkt_type == PKT_FLT) {
 | |
|             gxf_read_index(s, pkt_len);
 | |
|             continue;
 | |
|         }
 | |
|         if (pkt_type != PKT_MEDIA) {
 | |
|             url_fskip(pb, pkt_len);
 | |
|             continue;
 | |
|         }
 | |
|         if (pkt_len < 16) {
 | |
|             av_log(s, AV_LOG_ERROR, "invalid media packet length\n");
 | |
|             continue;
 | |
|         }
 | |
|         pkt_len -= 16;
 | |
|         track_type = get_byte(pb);
 | |
|         track_id = get_byte(pb);
 | |
|         stream_index = get_sindex(s, track_id, track_type);
 | |
|         if (stream_index < 0)
 | |
|             return stream_index;
 | |
|         st = s->streams[stream_index];
 | |
|         field_nr = get_be32(pb);
 | |
|         field_info = get_be32(pb);
 | |
|         get_be32(pb); // "timeline" field number
 | |
|         get_byte(pb); // flags
 | |
|         get_byte(pb); // reserved
 | |
|         if (st->codec->codec_id == CODEC_ID_PCM_S24LE ||
 | |
|             st->codec->codec_id == CODEC_ID_PCM_S16LE) {
 | |
|             int first = field_info >> 16;
 | |
|             int last  = field_info & 0xffff; // last is exclusive
 | |
|             int bps = av_get_bits_per_sample(st->codec->codec_id)>>3;
 | |
|             if (first <= last && last*bps <= pkt_len) {
 | |
|                 url_fskip(pb, first*bps);
 | |
|                 skip = pkt_len - last*bps;
 | |
|                 pkt_len = (last-first)*bps;
 | |
|             } else
 | |
|                 av_log(s, AV_LOG_ERROR, "invalid first and last sample values\n");
 | |
|         }
 | |
|         ret = av_get_packet(pb, pkt, pkt_len);
 | |
|         if (skip)
 | |
|             url_fskip(pb, skip);
 | |
|         pkt->stream_index = stream_index;
 | |
|         pkt->dts = field_nr;
 | |
|         return ret;
 | |
|     }
 | |
|     return AVERROR(EIO);
 | |
| }
 | |
| 
 | |
| static int gxf_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags) {
 | |
|     int res = 0;
 | |
|     uint64_t pos;
 | |
|     uint64_t maxlen = 100 * 1024 * 1024;
 | |
|     AVStream *st = s->streams[0];
 | |
|     int64_t start_time = s->streams[stream_index]->start_time;
 | |
|     int64_t found;
 | |
|     int idx;
 | |
|     if (timestamp < start_time) timestamp = start_time;
 | |
|     idx = av_index_search_timestamp(st, timestamp - start_time,
 | |
|                                     AVSEEK_FLAG_ANY | AVSEEK_FLAG_BACKWARD);
 | |
|     if (idx < 0)
 | |
|         return -1;
 | |
|     pos = st->index_entries[idx].pos;
 | |
|     if (idx < st->nb_index_entries - 2)
 | |
|         maxlen = st->index_entries[idx + 2].pos - pos;
 | |
|     maxlen = FFMAX(maxlen, 200 * 1024);
 | |
|     res = url_fseek(s->pb, pos, SEEK_SET);
 | |
|     if (res < 0)
 | |
|         return res;
 | |
|     found = gxf_resync_media(s, maxlen, -1, timestamp);
 | |
|     if (FFABS(found - timestamp) > 4)
 | |
|         return -1;
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| static int64_t gxf_read_timestamp(AVFormatContext *s, int stream_index,
 | |
|                                   int64_t *pos, int64_t pos_limit) {
 | |
|     ByteIOContext *pb = s->pb;
 | |
|     int64_t res;
 | |
|     if (url_fseek(pb, *pos, SEEK_SET) < 0)
 | |
|         return AV_NOPTS_VALUE;
 | |
|     res = gxf_resync_media(s, pos_limit - *pos, -1, -1);
 | |
|     *pos = url_ftell(pb);
 | |
|     return res;
 | |
| }
 | |
| 
 | |
| AVInputFormat gxf_demuxer = {
 | |
|     "gxf",
 | |
|     NULL_IF_CONFIG_SMALL("GXF format"),
 | |
|     0,
 | |
|     gxf_probe,
 | |
|     gxf_header,
 | |
|     gxf_packet,
 | |
|     NULL,
 | |
|     gxf_seek,
 | |
|     gxf_read_timestamp,
 | |
| };
 | 
