2 * Sierra VMD Format Demuxer
3 * Copyright (c) 2004 The ffmpeg Project
5 * This file is part of Libav.
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.
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.
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
24 * Sierra VMD file demuxer
25 * by Vladimir "VAG" Gneushev (vagsoft at mail.ru)
26 * for more information on the Sierra VMD file format, visit:
27 * http://www.pcisys.net/~melanson/codecs/
30 #include "libavutil/intreadwrite.h"
34 #define VMD_HEADER_SIZE 0x0330
35 #define BYTES_PER_FRAME_RECORD 16
40 unsigned int frame_size;
43 unsigned char frame_record[BYTES_PER_FRAME_RECORD];
46 typedef struct VmdDemuxContext {
47 int video_stream_index;
48 int audio_stream_index;
50 unsigned int frame_count;
51 unsigned int frames_per_block;
52 vmd_frame *frame_table;
53 unsigned int current_frame;
57 int64_t audio_sample_counter;
60 unsigned char vmd_header[VMD_HEADER_SIZE];
63 static int vmd_probe(AVProbeData *p)
68 /* check if the first 2 bytes of the file contain the appropriate size
69 * of a VMD header chunk */
70 if (AV_RL16(&p->buf[0]) != VMD_HEADER_SIZE - 2)
72 w = AV_RL16(&p->buf[12]);
73 h = AV_RL16(&p->buf[14]);
74 if (!w || w > 2048 || !h || h > 2048)
77 /* only return half certainty since this check is a bit sketchy */
78 return AVPROBE_SCORE_MAX / 2;
81 static int vmd_read_header(AVFormatContext *s)
83 VmdDemuxContext *vmd = s->priv_data;
84 AVIOContext *pb = s->pb;
85 AVStream *st = NULL, *vst;
86 unsigned int toc_offset;
87 unsigned char *raw_frame_table;
88 int raw_frame_table_size;
89 int64_t current_offset;
91 unsigned int total_frames;
92 int64_t current_audio_pts = 0;
93 unsigned char chunk[BYTES_PER_FRAME_RECORD];
97 /* fetch the main header, including the 2 header length bytes */
98 avio_seek(pb, 0, SEEK_SET);
99 if (avio_read(pb, vmd->vmd_header, VMD_HEADER_SIZE) != VMD_HEADER_SIZE)
102 if(vmd->vmd_header[24] == 'i' && vmd->vmd_header[25] == 'v' && vmd->vmd_header[26] == '3')
106 /* start up the decoders */
107 vst = avformat_new_stream(s, NULL);
109 return AVERROR(ENOMEM);
110 avpriv_set_pts_info(vst, 33, 1, 10);
111 vmd->video_stream_index = vst->index;
112 vst->codec->codec_type = AVMEDIA_TYPE_VIDEO;
113 vst->codec->codec_id = vmd->is_indeo3 ? CODEC_ID_INDEO3 : CODEC_ID_VMDVIDEO;
114 vst->codec->codec_tag = 0; /* no fourcc */
115 vst->codec->width = AV_RL16(&vmd->vmd_header[12]);
116 vst->codec->height = AV_RL16(&vmd->vmd_header[14]);
117 if(vmd->is_indeo3 && vst->codec->width > 320){
118 vst->codec->width >>= 1;
119 vst->codec->height >>= 1;
121 vst->codec->extradata_size = VMD_HEADER_SIZE;
122 vst->codec->extradata = av_mallocz(VMD_HEADER_SIZE + FF_INPUT_BUFFER_PADDING_SIZE);
123 memcpy(vst->codec->extradata, vmd->vmd_header, VMD_HEADER_SIZE);
125 /* if sample rate is 0, assume no audio */
126 vmd->sample_rate = AV_RL16(&vmd->vmd_header[804]);
127 if (vmd->sample_rate) {
128 st = avformat_new_stream(s, NULL);
130 return AVERROR(ENOMEM);
131 vmd->audio_stream_index = st->index;
132 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
133 st->codec->codec_id = CODEC_ID_VMDAUDIO;
134 st->codec->codec_tag = 0; /* no fourcc */
135 st->codec->channels = (vmd->vmd_header[811] & 0x80) ? 2 : 1;
136 st->codec->sample_rate = vmd->sample_rate;
137 st->codec->block_align = AV_RL16(&vmd->vmd_header[806]);
138 if (st->codec->block_align & 0x8000) {
139 st->codec->bits_per_coded_sample = 16;
140 st->codec->block_align = -(st->codec->block_align - 0x10000);
142 st->codec->bits_per_coded_sample = 8;
144 st->codec->bit_rate = st->codec->sample_rate *
145 st->codec->bits_per_coded_sample * st->codec->channels;
148 num = st->codec->block_align;
149 den = st->codec->sample_rate * st->codec->channels;
150 av_reduce(&den, &num, den, num, (1UL<<31)-1);
151 avpriv_set_pts_info(vst, 33, num, den);
152 avpriv_set_pts_info(st, 33, num, den);
155 toc_offset = AV_RL32(&vmd->vmd_header[812]);
156 vmd->frame_count = AV_RL16(&vmd->vmd_header[6]);
157 vmd->frames_per_block = AV_RL16(&vmd->vmd_header[18]);
158 avio_seek(pb, toc_offset, SEEK_SET);
160 raw_frame_table = NULL;
161 vmd->frame_table = NULL;
162 sound_buffers = AV_RL16(&vmd->vmd_header[808]);
163 raw_frame_table_size = vmd->frame_count * 6;
164 if(vmd->frame_count * vmd->frames_per_block >= UINT_MAX / sizeof(vmd_frame) - sound_buffers){
165 av_log(s, AV_LOG_ERROR, "vmd->frame_count * vmd->frames_per_block too large\n");
168 raw_frame_table = av_malloc(raw_frame_table_size);
169 vmd->frame_table = av_malloc((vmd->frame_count * vmd->frames_per_block + sound_buffers) * sizeof(vmd_frame));
170 if (!raw_frame_table || !vmd->frame_table) {
171 av_free(raw_frame_table);
172 av_free(vmd->frame_table);
173 return AVERROR(ENOMEM);
175 if (avio_read(pb, raw_frame_table, raw_frame_table_size) !=
176 raw_frame_table_size) {
177 av_free(raw_frame_table);
178 av_free(vmd->frame_table);
183 for (i = 0; i < vmd->frame_count; i++) {
185 current_offset = AV_RL32(&raw_frame_table[6 * i + 2]);
187 /* handle each entry in index block */
188 for (j = 0; j < vmd->frames_per_block; j++) {
192 avio_read(pb, chunk, BYTES_PER_FRAME_RECORD);
194 size = AV_RL32(&chunk[2]);
195 if(!size && type != 1)
198 case 1: /* Audio Chunk */
200 /* first audio chunk contains several audio buffers */
201 vmd->frame_table[total_frames].frame_offset = current_offset;
202 vmd->frame_table[total_frames].stream_index = vmd->audio_stream_index;
203 vmd->frame_table[total_frames].frame_size = size;
204 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
205 vmd->frame_table[total_frames].pts = current_audio_pts;
207 if(!current_audio_pts)
208 current_audio_pts += sound_buffers - 1;
212 case 2: /* Video Chunk */
213 vmd->frame_table[total_frames].frame_offset = current_offset;
214 vmd->frame_table[total_frames].stream_index = vmd->video_stream_index;
215 vmd->frame_table[total_frames].frame_size = size;
216 memcpy(vmd->frame_table[total_frames].frame_record, chunk, BYTES_PER_FRAME_RECORD);
217 vmd->frame_table[total_frames].pts = i;
221 current_offset += size;
225 av_free(raw_frame_table);
227 vmd->current_frame = 0;
228 vmd->frame_count = total_frames;
233 static int vmd_read_packet(AVFormatContext *s,
236 VmdDemuxContext *vmd = s->priv_data;
237 AVIOContext *pb = s->pb;
241 if (vmd->current_frame >= vmd->frame_count)
244 frame = &vmd->frame_table[vmd->current_frame];
245 /* position the stream (will probably be there already) */
246 avio_seek(pb, frame->frame_offset, SEEK_SET);
248 if (av_new_packet(pkt, frame->frame_size + BYTES_PER_FRAME_RECORD))
249 return AVERROR(ENOMEM);
250 pkt->pos= avio_tell(pb);
251 memcpy(pkt->data, frame->frame_record, BYTES_PER_FRAME_RECORD);
252 if(vmd->is_indeo3 && frame->frame_record[0] == 0x02)
253 ret = avio_read(pb, pkt->data, frame->frame_size);
255 ret = avio_read(pb, pkt->data + BYTES_PER_FRAME_RECORD,
258 if (ret != frame->frame_size) {
262 pkt->stream_index = frame->stream_index;
263 pkt->pts = frame->pts;
264 av_log(s, AV_LOG_DEBUG, " dispatching %s frame with %d bytes and pts %"PRId64"\n",
265 (frame->frame_record[0] == 0x02) ? "video" : "audio",
266 frame->frame_size + BYTES_PER_FRAME_RECORD,
269 vmd->current_frame++;
274 static int vmd_read_close(AVFormatContext *s)
276 VmdDemuxContext *vmd = s->priv_data;
278 av_free(vmd->frame_table);
283 AVInputFormat ff_vmd_demuxer = {
285 .long_name = NULL_IF_CONFIG_SMALL("Sierra VMD format"),
286 .priv_data_size = sizeof(VmdDemuxContext),
287 .read_probe = vmd_probe,
288 .read_header = vmd_read_header,
289 .read_packet = vmd_read_packet,
290 .read_close = vmd_read_close,