2 * Bethsoft VID format Demuxer
3 * Copyright (c) 2007 Nicholas Tung
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
24 * @brief Bethesda Softworks VID (.vid) file demuxer
25 * @author Nicholas Tung [ntung (at. ntung com] (2007-03)
26 * @see http://wiki.multimedia.cx/index.php?title=Bethsoft_VID
27 * @see http://www.svatopluk.com/andux/docs/dfvid.html
30 #include "libavutil/channel_layout.h"
31 #include "libavutil/intreadwrite.h"
34 #include "libavcodec/bethsoftvideo.h"
36 #define BVID_PALETTE_SIZE 3 * 256
38 #define DEFAULT_SAMPLE_RATE 11111
40 typedef struct BVID_DemuxContext
43 int sample_rate; /**< audio sample rate */
44 int width; /**< video width */
45 int height; /**< video height */
46 /** delay value between frames, added to individual frame delay.
47 * custom units, which will be added to other custom units (~=16ms according
48 * to free, unofficial documentation) */
49 int bethsoft_global_delay;
50 int video_index; /**< video stream index */
51 int audio_index; /**< audio stream index */
58 static int vid_probe(AVProbeData *p)
60 // little-endian VID tag, file starts with "VID\0"
61 if (AV_RL32(p->buf) != MKTAG('V', 'I', 'D', 0))
64 return AVPROBE_SCORE_MAX;
67 static int vid_read_header(AVFormatContext *s)
69 BVID_DemuxContext *vid = s->priv_data;
70 AVIOContext *pb = s->pb;
72 /* load main header. Contents:
74 * int16s: always_512, nframes, width, height, delay, always_14
77 vid->nframes = avio_rl16(pb);
78 vid->width = avio_rl16(pb);
79 vid->height = avio_rl16(pb);
80 vid->bethsoft_global_delay = avio_rl16(pb);
83 // wait until the first packet to create each stream
84 vid->video_index = -1;
85 vid->audio_index = -1;
86 vid->sample_rate = DEFAULT_SAMPLE_RATE;
87 s->ctx_flags |= AVFMTCTX_NOHEADER;
92 #define BUFFER_PADDING_SIZE 1000
93 static int read_frame(BVID_DemuxContext *vid, AVIOContext *pb, AVPacket *pkt,
94 uint8_t block_type, AVFormatContext *s)
96 uint8_t * vidbuf_start = NULL;
97 int vidbuf_nbytes = 0;
100 int position, duration, npixels;
101 unsigned int vidbuf_capacity;
105 if (vid->video_index < 0) {
106 st = avformat_new_stream(s, NULL);
108 return AVERROR(ENOMEM);
109 vid->video_index = st->index;
110 if (vid->audio_index < 0) {
111 av_log_ask_for_sample(s, "No audio packet before first video "
112 "packet. Using default video time base.\n");
114 avpriv_set_pts_info(st, 64, 185, vid->sample_rate);
115 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
116 st->codec->codec_id = AV_CODEC_ID_BETHSOFTVID;
117 st->codec->width = vid->width;
118 st->codec->height = vid->height;
120 st = s->streams[vid->video_index];
121 npixels = st->codec->width * st->codec->height;
123 vidbuf_start = av_malloc(vidbuf_capacity = BUFFER_PADDING_SIZE);
125 return AVERROR(ENOMEM);
127 // save the file position for the packet, include block type
128 position = avio_tell(pb) - 1;
130 vidbuf_start[vidbuf_nbytes++] = block_type;
132 // get the current packet duration
133 duration = vid->bethsoft_global_delay + avio_rl16(pb);
135 // set the y offset if it exists (decoder header data should be in data section)
136 if(block_type == VIDEO_YOFF_P_FRAME){
137 if (avio_read(pb, &vidbuf_start[vidbuf_nbytes], 2) != 2) {
145 vidbuf_start = av_fast_realloc(vidbuf_start, &vidbuf_capacity, vidbuf_nbytes + BUFFER_PADDING_SIZE);
147 return AVERROR(ENOMEM);
150 vidbuf_start[vidbuf_nbytes++] = code;
152 if(code >= 0x80){ // rle sequence
153 if(block_type == VIDEO_I_FRAME)
154 vidbuf_start[vidbuf_nbytes++] = avio_r8(pb);
155 } else if(code){ // plain sequence
156 if (avio_read(pb, &vidbuf_start[vidbuf_nbytes], code) != code) {
160 vidbuf_nbytes += code;
162 bytes_copied += code & 0x7F;
163 if(bytes_copied == npixels){ // sometimes no stop character is given, need to keep track of bytes copied
164 // may contain a 0 byte even if read all pixels
166 avio_seek(pb, -1, SEEK_CUR);
169 if (bytes_copied > npixels) {
170 ret = AVERROR_INVALIDDATA;
175 // copy data into packet
176 if ((ret = av_new_packet(pkt, vidbuf_nbytes)) < 0)
178 memcpy(pkt->data, vidbuf_start, vidbuf_nbytes);
179 av_free(vidbuf_start);
182 pkt->stream_index = vid->video_index;
183 pkt->duration = duration;
184 if (block_type == VIDEO_I_FRAME)
185 pkt->flags |= AV_PKT_FLAG_KEY;
187 /* if there is a new palette available, add it to packet side data */
189 uint8_t *pdata = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE,
192 memcpy(pdata, vid->palette, BVID_PALETTE_SIZE);
193 av_freep(&vid->palette);
196 vid->nframes--; // used to check if all the frames were read
199 av_free(vidbuf_start);
203 static int vid_read_packet(AVFormatContext *s,
206 BVID_DemuxContext *vid = s->priv_data;
207 AVIOContext *pb = s->pb;
208 unsigned char block_type;
212 if(vid->is_finished || url_feof(pb))
215 block_type = avio_r8(pb);
219 av_log(s, AV_LOG_WARNING, "discarding unused palette\n");
220 av_freep(&vid->palette);
222 vid->palette = av_malloc(BVID_PALETTE_SIZE);
224 return AVERROR(ENOMEM);
225 if (avio_read(pb, vid->palette, BVID_PALETTE_SIZE) != BVID_PALETTE_SIZE) {
226 av_freep(&vid->palette);
229 return vid_read_packet(s, pkt);
231 case FIRST_AUDIO_BLOCK:
233 // soundblaster DAC used for sample rate, as on specification page (link above)
234 vid->sample_rate = 1000000 / (256 - avio_r8(pb));
236 if (vid->audio_index < 0) {
237 AVStream *st = avformat_new_stream(s, NULL);
239 return AVERROR(ENOMEM);
240 vid->audio_index = st->index;
241 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
242 st->codec->codec_id = AV_CODEC_ID_PCM_U8;
243 st->codec->channels = 1;
244 st->codec->channel_layout = AV_CH_LAYOUT_MONO;
245 st->codec->bits_per_coded_sample = 8;
246 st->codec->sample_rate = vid->sample_rate;
247 st->codec->bit_rate = 8 * st->codec->sample_rate;
249 avpriv_set_pts_info(st, 64, 1, vid->sample_rate);
251 audio_length = avio_rl16(pb);
252 if ((ret_value = av_get_packet(pb, pkt, audio_length)) != audio_length) {
255 av_log(s, AV_LOG_ERROR, "incomplete audio block\n");
258 pkt->stream_index = vid->audio_index;
259 pkt->duration = audio_length;
260 pkt->flags |= AV_PKT_FLAG_KEY;
264 case VIDEO_YOFF_P_FRAME:
266 return read_frame(vid, pb, pkt, block_type, s);
269 if(vid->nframes != 0)
270 av_log(s, AV_LOG_VERBOSE, "reached terminating character but not all frames read.\n");
271 vid->is_finished = 1;
274 av_log(s, AV_LOG_ERROR, "unknown block (character = %c, decimal = %d, hex = %x)!!!\n",
275 block_type, block_type, block_type);
276 return AVERROR_INVALIDDATA;
280 static int vid_read_close(AVFormatContext *s)
282 BVID_DemuxContext *vid = s->priv_data;
283 av_freep(&vid->palette);
287 AVInputFormat ff_bethsoftvid_demuxer = {
288 .name = "bethsoftvid",
289 .long_name = NULL_IF_CONFIG_SMALL("Bethesda Softworks VID"),
290 .priv_data_size = sizeof(BVID_DemuxContext),
291 .read_probe = vid_probe,
292 .read_header = vid_read_header,
293 .read_packet = vid_read_packet,
294 .read_close = vid_read_close,