2 * 4X Technologies .4xm File Demuxer (no muxer)
3 * Copyright (c) 2003 The ffmpeg Project
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * 4X Technologies file demuxer
23 * by Mike Melanson (melanson@pcisys.net)
24 * for more information on the .4xm file format, visit:
25 * http://www.pcisys.net/~melanson/codecs/
30 #define RIFF_TAG MKTAG('R', 'I', 'F', 'F')
31 #define _4XMV_TAG MKTAG('4', 'X', 'M', 'V')
32 #define LIST_TAG MKTAG('L', 'I', 'S', 'T')
33 #define HEAD_TAG MKTAG('H', 'E', 'A', 'D')
34 #define TRK__TAG MKTAG('T', 'R', 'K', '_')
35 #define MOVI_TAG MKTAG('M', 'O', 'V', 'I')
36 #define VTRK_TAG MKTAG('V', 'T', 'R', 'K')
37 #define STRK_TAG MKTAG('S', 'T', 'R', 'K')
38 #define std__TAG MKTAG('s', 't', 'd', '_')
39 #define name_TAG MKTAG('n', 'a', 'm', 'e')
40 #define vtrk_TAG MKTAG('v', 't', 'r', 'k')
41 #define strk_TAG MKTAG('s', 't', 'r', 'k')
42 #define ifrm_TAG MKTAG('i', 'f', 'r', 'm')
43 #define pfrm_TAG MKTAG('p', 'f', 'r', 'm')
44 #define cfrm_TAG MKTAG('c', 'f', 'r', 'm')
45 #define snd__TAG MKTAG('s', 'n', 'd', '_')
47 #define vtrk_SIZE 0x44
48 #define strk_SIZE 0x28
50 #define GET_LIST_HEADER() \
51 fourcc_tag = get_le32(pb); \
52 size = get_le32(pb); \
53 if (fourcc_tag != LIST_TAG) \
54 return AVERROR_INVALIDDATA; \
55 fourcc_tag = get_le32(pb);
57 typedef struct AudioTrack {
65 typedef struct FourxmDemuxContext {
68 int video_stream_index;
79 static float get_le_float(unsigned char *buffer)
82 unsigned char *float_buffer = (unsigned char *)&f;
84 #ifdef WORDS_BIGENDIAN
85 float_buffer[0] = buffer[3];
86 float_buffer[1] = buffer[2];
87 float_buffer[2] = buffer[1];
88 float_buffer[3] = buffer[0];
90 float_buffer[0] = buffer[0];
91 float_buffer[1] = buffer[1];
92 float_buffer[2] = buffer[2];
93 float_buffer[3] = buffer[3];
99 static int fourxm_probe(AVProbeData *p)
101 if (p->buf_size < 12)
104 if ((LE_32(&p->buf[0]) != RIFF_TAG) ||
105 (LE_32(&p->buf[8]) != _4XMV_TAG))
108 return AVPROBE_SCORE_MAX;
111 static int fourxm_read_header(AVFormatContext *s,
112 AVFormatParameters *ap)
114 ByteIOContext *pb = &s->pb;
115 unsigned int fourcc_tag;
118 FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
119 unsigned char *header;
121 int current_track = -1;
124 fourxm->track_count = 0;
125 fourxm->tracks = NULL;
126 fourxm->selected_track = 0;
129 /* skip the first 3 32-bit numbers */
130 url_fseek(pb, 12, SEEK_CUR);
132 /* check for LIST-HEAD */
134 header_size = size - 4;
135 if (fourcc_tag != HEAD_TAG)
136 return AVERROR_INVALIDDATA;
138 /* allocate space for the header and load the whole thing */
139 header = av_malloc(header_size);
141 return AVERROR_NOMEM;
142 if (get_buffer(pb, header, header_size) != header_size)
145 /* take the lazy approach and search for any and all vtrk and strk chunks */
146 for (i = 0; i < header_size - 8; i++) {
147 fourcc_tag = LE_32(&header[i]);
148 size = LE_32(&header[i + 4]);
150 if (fourcc_tag == std__TAG) {
151 fourxm->fps = get_le_float(&header[i + 12]);
152 fourxm->video_pts_inc = (int)(90000.0 / fourxm->fps);
153 } else if (fourcc_tag == vtrk_TAG) {
154 /* check that there is enough data */
155 if (size != vtrk_SIZE) {
157 return AVERROR_INVALIDDATA;
159 fourxm->width = LE_32(&header[i + 36]);
160 fourxm->height = LE_32(&header[i + 40]);
163 /* allocate a new AVStream */
164 st = av_new_stream(s, 0);
166 return AVERROR_NOMEM;
167 av_set_pts_info(st, 33, 1, 90000);
169 fourxm->video_stream_index = st->index;
171 st->codec.frame_rate = fourxm->fps;
172 st->codec.frame_rate_base = 1.0;
173 st->codec.codec_type = CODEC_TYPE_VIDEO;
174 st->codec.codec_id = CODEC_ID_4XM;
175 st->codec.codec_tag = 0; /* no fourcc */
176 st->codec.width = fourxm->width;
177 st->codec.height = fourxm->height;
179 } else if (fourcc_tag == strk_TAG) {
180 /* check that there is enough data */
181 if (size != strk_SIZE) {
183 return AVERROR_INVALIDDATA;
185 current_track = LE_32(&header[i + 8]);
186 if (current_track + 1 > fourxm->track_count) {
187 fourxm->track_count = current_track + 1;
188 fourxm->tracks = av_realloc(fourxm->tracks,
189 fourxm->track_count * sizeof(AudioTrack));
190 if (!fourxm->tracks) {
192 return AVERROR_NOMEM;
195 fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
196 fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
197 fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
198 fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
201 /* allocate a new AVStream */
202 st = av_new_stream(s, current_track);
204 return AVERROR_NOMEM;
206 /* set the pts reference (1 pts = 1/90000) */
207 av_set_pts_info(st, 33, 1, 90000);
209 fourxm->tracks[current_track].stream_index = st->index;
211 st->codec.codec_type = CODEC_TYPE_AUDIO;
212 st->codec.codec_tag = 1;
213 st->codec.channels = fourxm->tracks[current_track].channels;
214 st->codec.sample_rate = fourxm->tracks[current_track].sample_rate;
215 st->codec.bits_per_sample = fourxm->tracks[current_track].bits;
216 st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
217 st->codec.bits_per_sample;
218 st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
219 if (fourxm->tracks[current_track].adpcm)
220 st->codec.codec_id = CODEC_ID_ADPCM_4XM;
221 else if (st->codec.bits_per_sample == 8)
222 st->codec.codec_id = CODEC_ID_PCM_U8;
224 st->codec.codec_id = CODEC_ID_PCM_S16LE;
230 /* skip over the LIST-MOVI chunk (which is where the stream should be */
232 if (fourcc_tag != MOVI_TAG)
233 return AVERROR_INVALIDDATA;
235 /* initialize context members */
236 fourxm->video_pts = -fourxm->video_pts_inc; /* first frame will push to 0 */
237 fourxm->audio_pts = 0;
242 static int fourxm_read_packet(AVFormatContext *s,
245 FourxmDemuxContext *fourxm = s->priv_data;
246 ByteIOContext *pb = &s->pb;
247 unsigned int fourcc_tag;
248 unsigned int size, out_size;
252 unsigned char header[8];
254 int audio_frame_count;
256 while (!packet_read) {
258 if ((ret = get_buffer(&s->pb, header, 8)) < 0)
260 fourcc_tag = LE_32(&header[0]);
261 size = LE_32(&header[4]);
264 switch (fourcc_tag) {
267 /* this is a good time to bump the video pts */
268 fourxm->video_pts += fourxm->video_pts_inc;
270 /* skip the LIST-* tag and move on to the next fourcc */
278 /* allocate 8 more bytes than 'size' to account for fourcc
280 if (av_new_packet(pkt, size + 8))
282 pkt->stream_index = fourxm->video_stream_index;
283 pkt->pts = fourxm->video_pts;
284 memcpy(pkt->data, header, 8);
285 ret = get_buffer(&s->pb, &pkt->data[8], size);
295 track_number = get_le32(pb);
296 out_size= get_le32(pb);
299 if (track_number == fourxm->selected_track) {
300 if (av_new_packet(pkt, size))
303 fourxm->tracks[fourxm->selected_track].stream_index;
304 pkt->pts = fourxm->audio_pts;
305 ret = get_buffer(&s->pb, pkt->data, size);
312 audio_frame_count = size;
313 if (fourxm->tracks[fourxm->selected_track].adpcm)
315 2 * (fourxm->tracks[fourxm->selected_track].channels);
317 fourxm->tracks[fourxm->selected_track].channels;
318 if (fourxm->tracks[fourxm->selected_track].adpcm)
319 audio_frame_count *= 2;
322 (fourxm->tracks[fourxm->selected_track].bits / 8);
323 pts_inc = audio_frame_count;
325 pts_inc /= fourxm->tracks[fourxm->selected_track].sample_rate;
326 fourxm->audio_pts += pts_inc;
329 url_fseek(pb, size, SEEK_CUR);
334 url_fseek(pb, size, SEEK_CUR);
341 static int fourxm_read_close(AVFormatContext *s)
343 FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
345 av_free(fourxm->tracks);
350 static AVInputFormat fourxm_iformat = {
352 "4X Technologies format",
353 sizeof(FourxmDemuxContext),
360 int fourxm_init(void)
362 av_register_input_format(&fourxm_iformat);