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))
65 return AVPROBE_SCORE_MAX
/ 4;
67 return AVPROBE_SCORE_MAX
;
70 static int vid_read_header(AVFormatContext
*s
)
72 BVID_DemuxContext
*vid
= s
->priv_data
;
73 AVIOContext
*pb
= s
->pb
;
75 /* load main header. Contents:
77 * int16s: always_512, nframes, width, height, delay, always_14
80 vid
->nframes
= avio_rl16(pb
);
81 vid
->width
= avio_rl16(pb
);
82 vid
->height
= avio_rl16(pb
);
83 vid
->bethsoft_global_delay
= avio_rl16(pb
);
86 // wait until the first packet to create each stream
87 vid
->video_index
= -1;
88 vid
->audio_index
= -1;
89 vid
->sample_rate
= DEFAULT_SAMPLE_RATE
;
90 s
->ctx_flags
|= AVFMTCTX_NOHEADER
;
95 #define BUFFER_PADDING_SIZE 1000
96 static int read_frame(BVID_DemuxContext
*vid
, AVIOContext
*pb
, AVPacket
*pkt
,
97 uint8_t block_type
, AVFormatContext
*s
)
99 uint8_t * vidbuf_start
= NULL
;
100 int vidbuf_nbytes
= 0;
102 int bytes_copied
= 0;
103 int position
, duration
, npixels
;
104 unsigned int vidbuf_capacity
;
108 if (vid
->video_index
< 0) {
109 st
= avformat_new_stream(s
, NULL
);
111 return AVERROR(ENOMEM
);
112 vid
->video_index
= st
->index
;
113 if (vid
->audio_index
< 0) {
114 avpriv_request_sample(s
, "Using default video time base since "
115 "having no audio packet before the first "
118 avpriv_set_pts_info(st
, 64, 185, vid
->sample_rate
);
119 st
->codec
->codec_type
= AVMEDIA_TYPE_VIDEO
;
120 st
->codec
->codec_id
= AV_CODEC_ID_BETHSOFTVID
;
121 st
->codec
->width
= vid
->width
;
122 st
->codec
->height
= vid
->height
;
124 st
= s
->streams
[vid
->video_index
];
125 npixels
= st
->codec
->width
* st
->codec
->height
;
127 vidbuf_start
= av_malloc(vidbuf_capacity
= BUFFER_PADDING_SIZE
);
129 return AVERROR(ENOMEM
);
131 // save the file position for the packet, include block type
132 position
= avio_tell(pb
) - 1;
134 vidbuf_start
[vidbuf_nbytes
++] = block_type
;
136 // get the current packet duration
137 duration
= vid
->bethsoft_global_delay
+ avio_rl16(pb
);
139 // set the y offset if it exists (decoder header data should be in data section)
140 if(block_type
== VIDEO_YOFF_P_FRAME
){
141 if (avio_read(pb
, &vidbuf_start
[vidbuf_nbytes
], 2) != 2) {
149 vidbuf_start
= av_fast_realloc(vidbuf_start
, &vidbuf_capacity
, vidbuf_nbytes
+ BUFFER_PADDING_SIZE
);
151 return AVERROR(ENOMEM
);
154 vidbuf_start
[vidbuf_nbytes
++] = code
;
156 if(code
>= 0x80){ // rle sequence
157 if(block_type
== VIDEO_I_FRAME
)
158 vidbuf_start
[vidbuf_nbytes
++] = avio_r8(pb
);
159 } else if(code
){ // plain sequence
160 if (avio_read(pb
, &vidbuf_start
[vidbuf_nbytes
], code
) != code
) {
164 vidbuf_nbytes
+= code
;
166 bytes_copied
+= code
& 0x7F;
167 if(bytes_copied
== npixels
){ // sometimes no stop character is given, need to keep track of bytes copied
168 // may contain a 0 byte even if read all pixels
170 avio_seek(pb
, -1, SEEK_CUR
);
173 if (bytes_copied
> npixels
) {
174 ret
= AVERROR_INVALIDDATA
;
179 // copy data into packet
180 if ((ret
= av_new_packet(pkt
, vidbuf_nbytes
)) < 0)
182 memcpy(pkt
->data
, vidbuf_start
, vidbuf_nbytes
);
185 pkt
->stream_index
= vid
->video_index
;
186 pkt
->duration
= duration
;
187 if (block_type
== VIDEO_I_FRAME
)
188 pkt
->flags
|= AV_PKT_FLAG_KEY
;
190 /* if there is a new palette available, add it to packet side data */
192 uint8_t *pdata
= av_packet_new_side_data(pkt
, AV_PKT_DATA_PALETTE
,
195 ret
= AVERROR(ENOMEM
);
196 av_log(s
, AV_LOG_ERROR
, "Failed to allocate palette side data\n");
199 memcpy(pdata
, vid
->palette
, BVID_PALETTE_SIZE
);
201 av_freep(&vid
->palette
);
204 vid
->nframes
--; // used to check if all the frames were read
206 av_free(vidbuf_start
);
210 static int vid_read_packet(AVFormatContext
*s
,
213 BVID_DemuxContext
*vid
= s
->priv_data
;
214 AVIOContext
*pb
= s
->pb
;
215 unsigned char block_type
;
219 if(vid
->is_finished
|| avio_feof(pb
))
222 block_type
= avio_r8(pb
);
226 av_log(s
, AV_LOG_WARNING
, "discarding unused palette\n");
227 av_freep(&vid
->palette
);
229 vid
->palette
= av_malloc(BVID_PALETTE_SIZE
);
231 return AVERROR(ENOMEM
);
232 if (avio_read(pb
, vid
->palette
, BVID_PALETTE_SIZE
) != BVID_PALETTE_SIZE
) {
233 av_freep(&vid
->palette
);
236 return vid_read_packet(s
, pkt
);
238 case FIRST_AUDIO_BLOCK
:
240 // soundblaster DAC used for sample rate, as on specification page (link above)
241 vid
->sample_rate
= 1000000 / (256 - avio_r8(pb
));
243 if (vid
->audio_index
< 0) {
244 AVStream
*st
= avformat_new_stream(s
, NULL
);
246 return AVERROR(ENOMEM
);
247 vid
->audio_index
= st
->index
;
248 st
->codec
->codec_type
= AVMEDIA_TYPE_AUDIO
;
249 st
->codec
->codec_id
= AV_CODEC_ID_PCM_U8
;
250 st
->codec
->channels
= 1;
251 st
->codec
->channel_layout
= AV_CH_LAYOUT_MONO
;
252 st
->codec
->bits_per_coded_sample
= 8;
253 st
->codec
->sample_rate
= vid
->sample_rate
;
254 st
->codec
->bit_rate
= 8 * st
->codec
->sample_rate
;
256 avpriv_set_pts_info(st
, 64, 1, vid
->sample_rate
);
258 audio_length
= avio_rl16(pb
);
259 if ((ret_value
= av_get_packet(pb
, pkt
, audio_length
)) != audio_length
) {
262 av_log(s
, AV_LOG_ERROR
, "incomplete audio block\n");
265 pkt
->stream_index
= vid
->audio_index
;
266 pkt
->duration
= audio_length
;
267 pkt
->flags
|= AV_PKT_FLAG_KEY
;
271 case VIDEO_YOFF_P_FRAME
:
273 return read_frame(vid
, pb
, pkt
, block_type
, s
);
276 if(vid
->nframes
!= 0)
277 av_log(s
, AV_LOG_VERBOSE
, "reached terminating character but not all frames read.\n");
278 vid
->is_finished
= 1;
281 av_log(s
, AV_LOG_ERROR
, "unknown block (character = %c, decimal = %d, hex = %x)!!!\n",
282 block_type
, block_type
, block_type
);
283 return AVERROR_INVALIDDATA
;
287 static int vid_read_close(AVFormatContext
*s
)
289 BVID_DemuxContext
*vid
= s
->priv_data
;
290 av_freep(&vid
->palette
);
294 AVInputFormat ff_bethsoftvid_demuxer
= {
295 .name
= "bethsoftvid",
296 .long_name
= NULL_IF_CONFIG_SMALL("Bethesda Softworks VID"),
297 .priv_data_size
= sizeof(BVID_DemuxContext
),
298 .read_probe
= vid_probe
,
299 .read_header
= vid_read_header
,
300 .read_packet
= vid_read_packet
,
301 .read_close
= vid_read_close
,