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 * @sa http://wiki.multimedia.cx/index.php?title=Bethsoft_VID
27 * @sa http://www.svatopluk.com/andux/docs/dfvid.html
31 #include "bethsoftvideo.h"
33 typedef struct BVID_DemuxContext
36 /** delay value between frames, added to individual frame delay.
37 * custom units, which will be added to other custom units (~=16ms according
38 * to free, unofficial documentation) */
39 int bethsoft_global_delay;
41 /** video presentation time stamp.
42 * delay = 16 milliseconds * (global_delay + per_frame_delay) */
49 static int vid_probe(AVProbeData *p)
51 // little endian VID tag, file starts with "VID\0"
52 if (AV_RL32(p->buf) != MKTAG('V', 'I', 'D', 0))
55 return AVPROBE_SCORE_MAX;
58 static int vid_read_header(AVFormatContext *s,
59 AVFormatParameters *ap)
61 BVID_DemuxContext *vid = s->priv_data;
62 ByteIOContext *pb = s->pb;
65 /* load main header. Contents:
67 * int16s: always_512, nframes, width, height, delay, always_14
69 url_fseek(pb, 5, SEEK_CUR);
70 vid->nframes = get_le16(pb);
72 stream = av_new_stream(s, 0);
74 return AVERROR(ENOMEM);
75 av_set_pts_info(stream, 32, 1, 60); // 16 ms increments, i.e. 60 fps
76 stream->codec->codec_type = CODEC_TYPE_VIDEO;
77 stream->codec->codec_id = CODEC_ID_BETHSOFTVID;
78 stream->codec->width = get_le16(pb);
79 stream->codec->height = get_le16(pb);
80 stream->codec->pix_fmt = PIX_FMT_PAL8;
81 vid->bethsoft_global_delay = get_le16(pb);
84 // done with video codec, set up audio codec
85 stream = av_new_stream(s, 0);
87 return AVERROR(ENOMEM);
88 stream->codec->codec_type = CODEC_TYPE_AUDIO;
89 stream->codec->codec_id = CODEC_ID_PCM_U8;
90 stream->codec->channels = 1;
91 stream->codec->sample_rate = 11025;
92 stream->codec->bits_per_sample = 8;
93 stream->codec->bit_rate = stream->codec->channels * stream->codec->sample_rate * stream->codec->bits_per_sample;
98 #define BUFFER_PADDING_SIZE 1000
99 static int read_frame(BVID_DemuxContext *vid, ByteIOContext *pb, AVPacket *pkt,
100 uint8_t block_type, AVFormatContext *s, int npixels)
102 uint8_t * vidbuf_start = NULL;
103 int vidbuf_nbytes = 0;
105 int bytes_copied = 0;
107 unsigned int vidbuf_capacity;
109 vidbuf_start = av_malloc(vidbuf_capacity = BUFFER_PADDING_SIZE);
111 return AVERROR(ENOMEM);
113 // save the file position for the packet, include block type
114 position = url_ftell(pb) - 1;
116 vidbuf_start[vidbuf_nbytes++] = block_type;
118 // get the video delay (next int16), and set the presentation time
119 vid->video_pts += vid->bethsoft_global_delay + get_le16(pb);
121 // set the y offset if it exists (decoder header data should be in data section)
122 if(block_type == VIDEO_YOFF_P_FRAME){
123 if(get_buffer(pb, &vidbuf_start[vidbuf_nbytes], 2) != 2)
129 vidbuf_start = av_fast_realloc(vidbuf_start, &vidbuf_capacity, vidbuf_nbytes + BUFFER_PADDING_SIZE);
131 return AVERROR(ENOMEM);
134 vidbuf_start[vidbuf_nbytes++] = code;
136 if(code >= 0x80){ // rle sequence
137 if(block_type == VIDEO_I_FRAME)
138 vidbuf_start[vidbuf_nbytes++] = get_byte(pb);
139 } else if(code){ // plain sequence
140 if(get_buffer(pb, &vidbuf_start[vidbuf_nbytes], code) != code)
142 vidbuf_nbytes += code;
144 bytes_copied += code & 0x7F;
145 if(bytes_copied == npixels){ // sometimes no stop character is given, need to keep track of bytes copied
146 // may contain a 0 byte even if read all pixels
148 url_fseek(pb, -1, SEEK_CUR);
151 if(bytes_copied > npixels)
155 // copy data into packet
156 if(av_new_packet(pkt, vidbuf_nbytes) < 0)
158 memcpy(pkt->data, vidbuf_start, vidbuf_nbytes);
159 av_free(vidbuf_start);
162 pkt->stream_index = 0; // use the video decoder, which was initialized as the first stream
163 pkt->pts = vid->video_pts;
165 vid->nframes--; // used to check if all the frames were read
166 return vidbuf_nbytes;
168 av_free(vidbuf_start);
172 static int vid_read_packet(AVFormatContext *s,
175 BVID_DemuxContext *vid = s->priv_data;
176 ByteIOContext *pb = s->pb;
177 unsigned char block_type;
181 if(vid->is_finished || url_feof(pb))
184 block_type = get_byte(pb);
187 url_fseek(pb, -1, SEEK_CUR); // include block type
188 ret_value = av_get_packet(pb, pkt, 3 * 256 + 1);
189 if(ret_value != 3 * 256 + 1){
193 pkt->stream_index = 0;
196 case FIRST_AUDIO_BLOCK:
198 // soundblaster DAC used for sample rate, as on specification page (link above)
199 s->streams[1]->codec->sample_rate = 1000000 / (256 - get_byte(pb));
200 s->streams[1]->codec->bit_rate = s->streams[1]->codec->channels * s->streams[1]->codec->sample_rate * s->streams[1]->codec->bits_per_sample;
202 audio_length = get_le16(pb);
203 ret_value = av_get_packet(pb, pkt, audio_length);
204 pkt->stream_index = 1;
205 return (ret_value != audio_length ? AVERROR(EIO) : ret_value);
208 case VIDEO_YOFF_P_FRAME:
210 return read_frame(vid, pb, pkt, block_type, s,
211 s->streams[0]->codec->width * s->streams[0]->codec->height);
214 if(vid->nframes != 0)
215 av_log(s, AV_LOG_VERBOSE, "reached terminating character but not all frames read.\n");
216 vid->is_finished = 1;
219 av_log(s, AV_LOG_ERROR, "unknown block (character = %c, decimal = %d, hex = %x)!!!\n",
220 block_type, block_type, block_type); return -1;
226 AVInputFormat bethsoftvid_demuxer = {
228 "Bethesda Softworks 'Daggerfall' VID format",
229 sizeof(BVID_DemuxContext),