pmpdec.c
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1 /*
2  * PMP demuxer
3  * Copyright (c) 2011 Reimar Döffinger
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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.
11  *
12  * Libav 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.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "avformat.h"
24 #include "internal.h"
25 
26 typedef struct PMPContext {
31  uint32_t *packet_sizes;
33 } PMPContext;
34 
35 static int pmp_probe(AVProbeData *p)
36 {
37  if (!memcmp(p->buf, "pmpm\1\0\0\0", 8))
38  return AVPROBE_SCORE_MAX;
39  return 0;
40 }
41 
43 {
44  PMPContext *pmp = s->priv_data;
45  AVIOContext *pb = s->pb;
46  int tb_num, tb_den;
47  int index_cnt;
48  int audio_codec_id = CODEC_ID_NONE;
49  int srate, channels;
50  int i;
51  uint64_t pos;
53  if (!vst)
54  return AVERROR(ENOMEM);
56  avio_skip(pb, 8);
57  switch (avio_rl32(pb)) {
58  case 0:
60  break;
61  case 1:
63  break;
64  default:
65  av_log(s, AV_LOG_ERROR, "Unsupported video format\n");
66  break;
67  }
68  index_cnt = avio_rl32(pb);
69  vst->codec->width = avio_rl32(pb);
70  vst->codec->height = avio_rl32(pb);
71 
72  tb_num = avio_rl32(pb);
73  tb_den = avio_rl32(pb);
74  avpriv_set_pts_info(vst, 32, tb_num, tb_den);
75  vst->nb_frames = index_cnt;
76  vst->duration = index_cnt;
77 
78  switch (avio_rl32(pb)) {
79  case 0:
80  audio_codec_id = CODEC_ID_MP3;
81  break;
82  case 1:
83  av_log(s, AV_LOG_WARNING, "AAC is not yet correctly supported\n");
84  audio_codec_id = CODEC_ID_AAC;
85  break;
86  default:
87  av_log(s, AV_LOG_ERROR, "Unsupported audio format\n");
88  break;
89  }
90  pmp->num_streams = avio_rl16(pb) + 1;
91  avio_skip(pb, 10);
92  srate = avio_rl32(pb);
93  channels = avio_rl32(pb) + 1;
94  for (i = 1; i < pmp->num_streams; i++) {
96  if (!ast)
97  return AVERROR(ENOMEM);
99  ast->codec->codec_id = audio_codec_id;
100  ast->codec->channels = channels;
101  ast->codec->sample_rate = srate;
102  avpriv_set_pts_info(ast, 32, 1, srate);
103  }
104  pos = avio_tell(pb) + 4 * index_cnt;
105  for (i = 0; i < index_cnt; i++) {
106  int size = avio_rl32(pb);
107  int flags = size & 1 ? AVINDEX_KEYFRAME : 0;
108  size >>= 1;
109  av_add_index_entry(vst, pos, i, size, 0, flags);
110  pos += size;
111  }
112  return 0;
113 }
114 
115 static int pmp_packet(AVFormatContext *s, AVPacket *pkt)
116 {
117  PMPContext *pmp = s->priv_data;
118  AVIOContext *pb = s->pb;
119  int ret = 0;
120  int i;
121 
122  if (pb->eof_reached)
123  return AVERROR_EOF;
124  if (pmp->cur_stream == 0) {
125  int num_packets;
126  pmp->audio_packets = avio_r8(pb);
127  num_packets = (pmp->num_streams - 1) * pmp->audio_packets + 1;
128  avio_skip(pb, 8);
129  pmp->current_packet = 0;
131  &pmp->packet_sizes_alloc,
132  num_packets * sizeof(*pmp->packet_sizes));
133  if (!pmp->packet_sizes_alloc) {
134  av_log(s, AV_LOG_ERROR, "Cannot (re)allocate packet buffer\n");
135  return AVERROR(ENOMEM);
136  }
137  for (i = 0; i < num_packets; i++)
138  pmp->packet_sizes[i] = avio_rl32(pb);
139  }
140  ret = av_get_packet(pb, pkt, pmp->packet_sizes[pmp->current_packet]);
141  if (ret > 0) {
142  ret = 0;
143  // FIXME: this is a hack that should be removed once
144  // compute_pkt_fields() can handle timestamps properly
145  if (pmp->cur_stream == 0)
146  pkt->dts = s->streams[0]->cur_dts++;
147  pkt->stream_index = pmp->cur_stream;
148  }
149  pmp->current_packet++;
150  if (pmp->current_packet == 1 || pmp->current_packet > pmp->audio_packets)
151  pmp->cur_stream = (pmp->cur_stream + 1) % pmp->num_streams;
152 
153  return ret;
154 }
155 
156 static int pmp_seek(AVFormatContext *s, int stream_idx, int64_t ts, int flags)
157 {
158  PMPContext *pmp = s->priv_data;
159  pmp->cur_stream = 0;
160  // fallback to default seek now
161  return -1;
162 }
163 
165 {
166  PMPContext *pmp = s->priv_data;
167  av_freep(&pmp->packet_sizes);
168  return 0;
169 }
170 
172  .name = "pmp",
173  .long_name = NULL_IF_CONFIG_SMALL("Playstation Portable PMP format"),
174  .priv_data_size = sizeof(PMPContext),
178  .read_seek = pmp_seek,
180 };