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.
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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 */
53 uint8_t palette[BVID_PALETTE_SIZE];
59 static int vid_probe(const AVProbeData *p)
61 // little-endian VID tag, file starts with "VID\0"
62 if (AV_RL32(p->buf) != MKTAG('V', 'I', 'D', 0))
66 return AVPROBE_SCORE_MAX / 4;
68 return AVPROBE_SCORE_MAX;
71 static int vid_read_header(AVFormatContext *s)
73 BVID_DemuxContext *vid = s->priv_data;
74 AVIOContext *pb = s->pb;
76 /* load main header. Contents:
78 * int16s: always_512, nframes, width, height, delay, always_14
81 vid->nframes = avio_rl16(pb);
82 vid->width = avio_rl16(pb);
83 vid->height = avio_rl16(pb);
84 vid->bethsoft_global_delay = avio_rl16(pb);
87 // wait until the first packet to create each stream
88 vid->video_index = -1;
89 vid->audio_index = -1;
90 vid->sample_rate = DEFAULT_SAMPLE_RATE;
91 s->ctx_flags |= AVFMTCTX_NOHEADER;
96 #define BUFFER_PADDING_SIZE 1000
97 static int read_frame(BVID_DemuxContext *vid, AVIOContext *pb, AVPacket *pkt,
98 uint8_t block_type, AVFormatContext *s)
100 uint8_t * vidbuf_start = NULL;
101 int vidbuf_nbytes = 0;
103 int bytes_copied = 0;
104 int position, duration, npixels;
105 unsigned int vidbuf_capacity;
109 if (vid->video_index < 0) {
110 st = avformat_new_stream(s, NULL);
112 return AVERROR(ENOMEM);
113 vid->video_index = st->index;
114 if (vid->audio_index < 0) {
115 avpriv_request_sample(s, "Using default video time base since "
116 "having no audio packet before the first "
119 avpriv_set_pts_info(st, 64, 185, vid->sample_rate);
120 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
121 st->codecpar->codec_id = AV_CODEC_ID_BETHSOFTVID;
122 st->codecpar->width = vid->width;
123 st->codecpar->height = vid->height;
125 st = s->streams[vid->video_index];
126 npixels = st->codecpar->width * st->codecpar->height;
128 vidbuf_start = av_malloc(vidbuf_capacity = BUFFER_PADDING_SIZE);
130 return AVERROR(ENOMEM);
132 // save the file position for the packet, include block type
133 position = avio_tell(pb) - 1;
135 vidbuf_start[vidbuf_nbytes++] = block_type;
137 // get the current packet duration
138 duration = vid->bethsoft_global_delay + avio_rl16(pb);
140 // set the y offset if it exists (decoder header data should be in data section)
141 if(block_type == VIDEO_YOFF_P_FRAME){
142 if (avio_read(pb, &vidbuf_start[vidbuf_nbytes], 2) != 2) {
150 uint8_t *tmp = av_fast_realloc(vidbuf_start, &vidbuf_capacity,
151 vidbuf_nbytes + BUFFER_PADDING_SIZE);
153 ret = AVERROR(ENOMEM);
159 vidbuf_start[vidbuf_nbytes++] = code;
161 if(code >= 0x80){ // rle sequence
162 if(block_type == VIDEO_I_FRAME)
163 vidbuf_start[vidbuf_nbytes++] = avio_r8(pb);
164 } else if(code){ // plain sequence
165 if (avio_read(pb, &vidbuf_start[vidbuf_nbytes], code) != code) {
169 vidbuf_nbytes += code;
171 bytes_copied += code & 0x7F;
172 if(bytes_copied == npixels){ // sometimes no stop character is given, need to keep track of bytes copied
173 // may contain a 0 byte even if read all pixels
175 avio_seek(pb, -1, SEEK_CUR);
178 if (bytes_copied > npixels) {
179 ret = AVERROR_INVALIDDATA;
184 // copy data into packet
185 if ((ret = av_new_packet(pkt, vidbuf_nbytes)) < 0)
187 memcpy(pkt->data, vidbuf_start, vidbuf_nbytes);
190 pkt->stream_index = vid->video_index;
191 pkt->duration = duration;
192 if (block_type == VIDEO_I_FRAME)
193 pkt->flags |= AV_PKT_FLAG_KEY;
195 /* if there is a new palette available, add it to packet side data */
196 if (vid->has_palette) {
197 uint8_t *pdata = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE,
200 ret = AVERROR(ENOMEM);
201 av_log(s, AV_LOG_ERROR, "Failed to allocate palette side data\n");
204 memcpy(pdata, vid->palette, BVID_PALETTE_SIZE);
205 vid->has_palette = 0;
208 vid->nframes--; // used to check if all the frames were read
210 av_free(vidbuf_start);
214 static int vid_read_packet(AVFormatContext *s,
217 BVID_DemuxContext *vid = s->priv_data;
218 AVIOContext *pb = s->pb;
219 unsigned char block_type;
223 if(vid->is_finished || avio_feof(pb))
226 block_type = avio_r8(pb);
229 if (vid->has_palette) {
230 av_log(s, AV_LOG_WARNING, "discarding unused palette\n");
231 vid->has_palette = 0;
233 if (avio_read(pb, vid->palette, BVID_PALETTE_SIZE) != BVID_PALETTE_SIZE) {
236 vid->has_palette = 1;
237 return vid_read_packet(s, pkt);
239 case FIRST_AUDIO_BLOCK:
241 // soundblaster DAC used for sample rate, as on specification page (link above)
242 vid->sample_rate = 1000000 / (256 - avio_r8(pb));
244 if (vid->audio_index < 0) {
245 AVStream *st = avformat_new_stream(s, NULL);
247 return AVERROR(ENOMEM);
248 vid->audio_index = st->index;
249 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
250 st->codecpar->codec_id = AV_CODEC_ID_PCM_U8;
251 st->codecpar->channels = 1;
252 st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
253 st->codecpar->bits_per_coded_sample = 8;
254 st->codecpar->sample_rate = vid->sample_rate;
255 st->codecpar->bit_rate = 8 * st->codecpar->sample_rate;
257 avpriv_set_pts_info(st, 64, 1, vid->sample_rate);
259 audio_length = avio_rl16(pb);
260 if ((ret_value = av_get_packet(pb, pkt, audio_length)) != audio_length) {
263 av_log(s, AV_LOG_ERROR, "incomplete audio block\n");
266 pkt->stream_index = vid->audio_index;
267 pkt->duration = audio_length;
268 pkt->flags |= AV_PKT_FLAG_KEY;
272 case VIDEO_YOFF_P_FRAME:
274 return read_frame(vid, pb, pkt, block_type, s);
277 if(vid->nframes != 0)
278 av_log(s, AV_LOG_VERBOSE, "reached terminating character but not all frames read.\n");
279 vid->is_finished = 1;
282 av_log(s, AV_LOG_ERROR, "unknown block (character = %c, decimal = %d, hex = %x)!!!\n",
283 block_type, block_type, block_type);
284 return AVERROR_INVALIDDATA;
288 AVInputFormat ff_bethsoftvid_demuxer = {
289 .name = "bethsoftvid",
290 .long_name = NULL_IF_CONFIG_SMALL("Bethesda Softworks VID"),
291 .priv_data_size = sizeof(BVID_DemuxContext),
292 .read_probe = vid_probe,
293 .read_header = vid_read_header,
294 .read_packet = vid_read_packet,