Merge branch 'master' of http://repo.or.cz/r/FFMpeg-mirror
[FFMpeg-mirror/DVCPRO-HD.git] / libavformat / pva.c
blob32827d43e82de0a7629cdaa13588e0d5da7582ce
1 /*
2 * TechnoTrend PVA (.pva) demuxer
3 * Copyright (c) 2007, 2008 Ivo van Poorten
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "avformat.h"
23 #include "mpeg.h"
25 #define PVA_MAX_PAYLOAD_LENGTH 0x17f8
26 #define PVA_VIDEO_PAYLOAD 0x01
27 #define PVA_AUDIO_PAYLOAD 0x02
28 #define PVA_MAGIC (('A' << 8) + 'V')
30 typedef struct {
31 int continue_pes;
32 } PVAContext;
34 static int pva_probe(AVProbeData * pd) {
35 unsigned char *buf = pd->buf;
37 if (AV_RB16(buf) == PVA_MAGIC && buf[2] && buf[2] < 3 && buf[4] == 0x55)
38 return AVPROBE_SCORE_MAX / 2;
40 return 0;
43 static int pva_read_header(AVFormatContext *s, AVFormatParameters *ap) {
44 AVStream *st;
46 if (!(st = av_new_stream(s, 0)))
47 return AVERROR(ENOMEM);
48 st->codec->codec_type = CODEC_TYPE_VIDEO;
49 st->codec->codec_id = CODEC_ID_MPEG2VIDEO;
50 st->need_parsing = AVSTREAM_PARSE_FULL;
51 av_set_pts_info(st, 32, 1, 90000);
52 av_add_index_entry(st, 0, 0, 0, 0, AVINDEX_KEYFRAME);
54 if (!(st = av_new_stream(s, 1)))
55 return AVERROR(ENOMEM);
56 st->codec->codec_type = CODEC_TYPE_AUDIO;
57 st->codec->codec_id = CODEC_ID_MP2;
58 st->need_parsing = AVSTREAM_PARSE_HEADERS;
59 av_set_pts_info(st, 33, 1, 90000);
60 av_add_index_entry(st, 0, 0, 0, 0, AVINDEX_KEYFRAME);
62 /* the parameters will be extracted from the compressed bitstream */
63 return 0;
66 #define pva_log if (read_packet) av_log
68 static int read_part_of_packet(AVFormatContext *s, int64_t *pts,
69 int *len, int *strid, int read_packet) {
70 ByteIOContext *pb = s->pb;
71 PVAContext *pvactx = s->priv_data;
72 int syncword, streamid, reserved, flags, length, pts_flag;
73 int64_t pva_pts = AV_NOPTS_VALUE, startpos;
75 recover:
76 startpos = url_ftell(pb);
78 syncword = get_be16(pb);
79 streamid = get_byte(pb);
80 get_byte(pb); /* counter not used */
81 reserved = get_byte(pb);
82 flags = get_byte(pb);
83 length = get_be16(pb);
85 pts_flag = flags & 0x10;
87 if (syncword != PVA_MAGIC) {
88 pva_log(s, AV_LOG_ERROR, "invalid syncword\n");
89 return AVERROR(EIO);
91 if (streamid != PVA_VIDEO_PAYLOAD && streamid != PVA_AUDIO_PAYLOAD) {
92 pva_log(s, AV_LOG_ERROR, "invalid streamid\n");
93 return AVERROR(EIO);
95 if (reserved != 0x55) {
96 pva_log(s, AV_LOG_WARNING, "expected reserved byte to be 0x55\n");
98 if (length > PVA_MAX_PAYLOAD_LENGTH) {
99 pva_log(s, AV_LOG_ERROR, "invalid payload length %u\n", length);
100 return AVERROR(EIO);
103 if (streamid == PVA_VIDEO_PAYLOAD && pts_flag) {
104 pva_pts = get_be32(pb);
105 length -= 4;
106 } else if (streamid == PVA_AUDIO_PAYLOAD) {
107 /* PVA Audio Packets either start with a signaled PES packet or
108 * are a continuation of the previous PES packet. New PES packets
109 * always start at the beginning of a PVA Packet, never somewhere in
110 * the middle. */
111 if (!pvactx->continue_pes) {
112 int pes_signal, pes_header_data_length, pes_packet_length,
113 pes_flags;
114 unsigned char pes_header_data[256];
116 pes_signal = get_be24(pb);
117 get_byte(pb);
118 pes_packet_length = get_be16(pb);
119 pes_flags = get_be16(pb);
120 pes_header_data_length = get_byte(pb);
122 if (pes_signal != 1) {
123 pva_log(s, AV_LOG_WARNING, "expected signaled PES packet, "
124 "trying to recover\n");
125 url_fskip(pb, length - 9);
126 if (!read_packet)
127 return AVERROR(EIO);
128 goto recover;
131 get_buffer(pb, pes_header_data, pes_header_data_length);
132 length -= 9 + pes_header_data_length;
134 pes_packet_length -= 3 + pes_header_data_length;
136 pvactx->continue_pes = pes_packet_length;
138 if (pes_flags & 0x80 && (pes_header_data[0] & 0xf0) == 0x20)
139 pva_pts = ff_parse_pes_pts(pes_header_data);
142 pvactx->continue_pes -= length;
144 if (pvactx->continue_pes < 0) {
145 pva_log(s, AV_LOG_WARNING, "audio data corruption\n");
146 pvactx->continue_pes = 0;
150 if (pva_pts != AV_NOPTS_VALUE)
151 av_add_index_entry(s->streams[streamid-1], startpos, pva_pts, 0, 0, AVINDEX_KEYFRAME);
153 *pts = pva_pts;
154 *len = length;
155 *strid = streamid;
156 return 0;
159 static int pva_read_packet(AVFormatContext *s, AVPacket *pkt) {
160 ByteIOContext *pb = s->pb;
161 int64_t pva_pts;
162 int ret, length, streamid;
164 if (read_part_of_packet(s, &pva_pts, &length, &streamid, 1) < 0 ||
165 (ret = av_get_packet(pb, pkt, length)) <= 0)
166 return AVERROR(EIO);
168 pkt->stream_index = streamid - 1;
169 pkt->pts = pva_pts;
171 return ret;
174 static int64_t pva_read_timestamp(struct AVFormatContext *s, int stream_index,
175 int64_t *pos, int64_t pos_limit) {
176 ByteIOContext *pb = s->pb;
177 PVAContext *pvactx = s->priv_data;
178 int length, streamid;
179 int64_t res;
181 pos_limit = FFMIN(*pos+PVA_MAX_PAYLOAD_LENGTH*8, (uint64_t)*pos+pos_limit);
183 while (*pos < pos_limit) {
184 res = AV_NOPTS_VALUE;
185 url_fseek(pb, *pos, SEEK_SET);
187 pvactx->continue_pes = 0;
188 if (read_part_of_packet(s, &res, &length, &streamid, 0)) {
189 (*pos)++;
190 continue;
192 if (streamid - 1 != stream_index || res == AV_NOPTS_VALUE) {
193 *pos = url_ftell(pb) + length;
194 continue;
196 break;
199 pvactx->continue_pes = 0;
200 return res;
203 AVInputFormat pva_demuxer = {
204 "pva",
205 NULL_IF_CONFIG_SMALL("TechnoTrend PVA file and stream format"),
206 sizeof(PVAContext),
207 pva_probe,
208 pva_read_header,
209 pva_read_packet,
210 .read_timestamp = pva_read_timestamp