3 * Copyright (c) 2007 Konstantin Shishkov
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 #include "libavutil/intreadwrite.h"
29 #define DXA_EXTRA_SIZE 9
31 typedef struct DXAContext {
36 int64_t wavpos, vidpos;
40 static int dxa_probe(AVProbeData *p)
45 w = AV_RB16(p->buf + 11);
46 h = AV_RB16(p->buf + 13);
47 /* check file header */
48 if (p->buf[0] == 'D' && p->buf[1] == 'E' &&
49 p->buf[2] == 'X' && p->buf[3] == 'A' &&
50 w && w <= 2048 && h && h <= 2048)
51 return AVPROBE_SCORE_MAX;
56 static int dxa_read_header(AVFormatContext *s)
58 AVIOContext *pb = s->pb;
59 DXAContext *c = s->priv_data;
69 if (tag != MKTAG('D', 'E', 'X', 'A'))
70 return AVERROR_INVALIDDATA;
72 c->frames = avio_rb16(pb);
74 av_log(s, AV_LOG_ERROR, "File contains no frames ???\n");
75 return AVERROR_INVALIDDATA;
93 st = avformat_new_stream(s, NULL);
95 return AVERROR(ENOMEM);
97 // Parse WAV data header
98 if(avio_rl32(pb) == MKTAG('W', 'A', 'V', 'E')){
101 size = avio_rb32(pb);
102 c->vidpos = avio_tell(pb) + size;
104 fsize = avio_rl32(pb);
106 ast = avformat_new_stream(s, NULL);
108 return AVERROR(ENOMEM);
109 ret = ff_get_wav_header(s, pb, ast->codec, fsize, 0);
112 if (ast->codec->sample_rate > 0)
113 avpriv_set_pts_info(ast, 64, 1, ast->codec->sample_rate);
115 while(avio_tell(pb) < c->vidpos && !avio_feof(pb)){
117 fsize = avio_rl32(pb);
118 if(tag == MKTAG('d', 'a', 't', 'a')) break;
119 avio_skip(pb, fsize);
121 c->bpc = (fsize + c->frames - 1) / c->frames;
122 if(ast->codec->block_align)
123 c->bpc = ((c->bpc + ast->codec->block_align - 1) / ast->codec->block_align) * ast->codec->block_align;
124 c->bytes_left = fsize;
125 c->wavpos = avio_tell(pb);
126 avio_seek(pb, c->vidpos, SEEK_SET);
129 /* now we are ready: build format streams */
130 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
131 st->codec->codec_id = AV_CODEC_ID_DXA;
132 st->codec->width = w;
133 st->codec->height = h;
134 av_reduce(&den, &num, den, num, (1UL<<31)-1);
135 avpriv_set_pts_info(st, 33, num, den);
136 /* flags & 0x80 means that image is interlaced,
137 * flags & 0x40 means that image has double height
138 * either way set true height
141 st->codec->height >>= 1;
143 c->readvid = !c->has_sound;
144 c->vidpos = avio_tell(pb);
146 s->duration = (int64_t)c->frames * AV_TIME_BASE * num / den;
147 av_log(s, AV_LOG_DEBUG, "%d frame(s)\n",c->frames);
152 static int dxa_read_packet(AVFormatContext *s, AVPacket *pkt)
154 DXAContext *c = s->priv_data;
157 uint8_t buf[DXA_EXTRA_SIZE], pal[768+4];
160 if(!c->readvid && c->has_sound && c->bytes_left){
162 avio_seek(s->pb, c->wavpos, SEEK_SET);
163 size = FFMIN(c->bytes_left, c->bpc);
164 ret = av_get_packet(s->pb, pkt, size);
165 pkt->stream_index = 1;
168 c->bytes_left -= size;
169 c->wavpos = avio_tell(s->pb);
172 avio_seek(s->pb, c->vidpos, SEEK_SET);
173 while(!avio_feof(s->pb) && c->frames){
174 if ((ret = avio_read(s->pb, buf, 4)) != 4) {
175 av_log(s, AV_LOG_ERROR, "failed reading chunk type\n");
176 return ret < 0 ? ret : AVERROR_INVALIDDATA;
178 switch(AV_RL32(buf)){
179 case MKTAG('N', 'U', 'L', 'L'):
180 if(av_new_packet(pkt, 4 + pal_size) < 0)
181 return AVERROR(ENOMEM);
182 pkt->stream_index = 0;
183 if(pal_size) memcpy(pkt->data, pal, pal_size);
184 memcpy(pkt->data + pal_size, buf, 4);
186 c->vidpos = avio_tell(s->pb);
189 case MKTAG('C', 'M', 'A', 'P'):
192 avio_read(s->pb, pal + 4, 768);
194 case MKTAG('F', 'R', 'A', 'M'):
195 if ((ret = avio_read(s->pb, buf + 4, DXA_EXTRA_SIZE - 4)) != DXA_EXTRA_SIZE - 4) {
196 av_log(s, AV_LOG_ERROR, "failed reading dxa_extra\n");
197 return ret < 0 ? ret : AVERROR_INVALIDDATA;
199 size = AV_RB32(buf + 5);
201 av_log(s, AV_LOG_ERROR, "Frame size is too big: %"PRIu32"\n",
203 return AVERROR_INVALIDDATA;
205 if(av_new_packet(pkt, size + DXA_EXTRA_SIZE + pal_size) < 0)
206 return AVERROR(ENOMEM);
207 memcpy(pkt->data + pal_size, buf, DXA_EXTRA_SIZE);
208 ret = avio_read(s->pb, pkt->data + DXA_EXTRA_SIZE + pal_size, size);
213 if(pal_size) memcpy(pkt->data, pal, pal_size);
214 pkt->stream_index = 0;
216 c->vidpos = avio_tell(s->pb);
220 av_log(s, AV_LOG_ERROR, "Unknown tag %c%c%c%c\n", buf[0], buf[1], buf[2], buf[3]);
221 return AVERROR_INVALIDDATA;
227 AVInputFormat ff_dxa_demuxer = {
229 .long_name = NULL_IF_CONFIG_SMALL("DXA"),
230 .priv_data_size = sizeof(DXAContext),
231 .read_probe = dxa_probe,
232 .read_header = dxa_read_header,
233 .read_packet = dxa_read_packet,