* mtv demuxer
* Copyright (c) 2006 Reynaldo H. Verdejo Pinochet
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file mtv.c
+ * @file
* MTV demuxer.
*/
#include "libavutil/bswap.h"
+#include "libavutil/intreadwrite.h"
#include "avformat.h"
+#include "internal.h"
#define MTV_ASUBCHUNK_DATA_SIZE 500
#define MTV_HEADER_SIZE 512
#define MTV_AUDIO_PADDING_SIZE 12
#define AUDIO_SAMPLING_RATE 44100
-#define VIDEO_SID 0
-#define AUDIO_SID 1
typedef struct MTVDemuxContext {
- unsigned int file_size; ///< filesize, not always right
- unsigned int segments; ///< number of 512 byte segments
- unsigned int audio_identifier; ///< 'MP3' on all files I have seen
- unsigned int audio_br; ///< bitrate of audio chanel (mp3)
- unsigned int img_colorfmt; ///< frame colorfmt rgb 565/555
- unsigned int img_bpp; ///< frame bits per pixel
- unsigned int img_width; //
- unsigned int img_height; //
- unsigned int img_segment_size; ///< size of image segment
- unsigned int video_fps; //
- unsigned int audio_subsegments; ///< audio subsegments on one segment
-
- uint8_t audio_packet_count;
+ unsigned int file_size; ///< filesize, not always right
+ unsigned int segments; ///< number of 512 byte segments
+ unsigned int audio_identifier; ///< 'MP3' on all files I have seen
+ unsigned int audio_br; ///< bitrate of audio channel (mp3)
+ unsigned int img_colorfmt; ///< frame colorfmt rgb 565/555
+ unsigned int img_bpp; ///< frame bits per pixel
+ unsigned int img_width; //
+ unsigned int img_height; //
+ unsigned int img_segment_size; ///< size of image segment
+ unsigned int video_fps; //
+ unsigned int full_segment_size;
} MTVDemuxContext;
static int mtv_probe(AVProbeData *p)
{
/* Magic is 'AMV' */
+ if (*p->buf != 'A' || *(p->buf + 1) != 'M' || *(p->buf + 2) != 'V')
+ return 0;
- if(*(p->buf) != 'A' || *(p->buf+1) != 'M' || *(p->buf+2) != 'V')
+ /* Check for nonzero in bpp and (width|height) header fields */
+ if(!(p->buf[51] && AV_RL16(&p->buf[52]) | AV_RL16(&p->buf[54])))
return 0;
+ /* If width or height are 0 then imagesize header field should not */
+ if(!AV_RL16(&p->buf[52]) || !AV_RL16(&p->buf[54]))
+ {
+ if(!!AV_RL16(&p->buf[56]))
+ return AVPROBE_SCORE_EXTENSION;
+ else
+ return 0;
+ }
+
+ if(p->buf[51] != 16)
+ return AVPROBE_SCORE_EXTENSION / 2; // But we are going to assume 16bpp anyway ..
+
return AVPROBE_SCORE_MAX;
}
-static int mtv_read_header(AVFormatContext *s, AVFormatParameters *ap)
+static int mtv_read_header(AVFormatContext *s)
{
- MTVDemuxContext *mtv = s->priv_data;
- ByteIOContext *pb = s->pb;
- AVStream *st;
-
-
- url_fskip(pb, 3);
- mtv->file_size = get_le32(pb);
- mtv->segments = get_le32(pb);
- url_fskip(pb, 32);
- mtv->audio_identifier = get_le24(pb);
- mtv->audio_br = get_le16(pb);
- mtv->img_colorfmt = get_le24(pb);
- mtv->img_bpp = get_byte(pb);
- mtv->img_width = get_le16(pb);
- mtv->img_height = get_le16(pb);
- mtv->img_segment_size = get_le16(pb);
- url_fskip(pb, 4);
- mtv->audio_subsegments = get_le16(pb);
- mtv->video_fps = (mtv->audio_br / 4) / mtv->audio_subsegments;
-
- /* FIXME Add sanity check here */
+ MTVDemuxContext *mtv = s->priv_data;
+ AVIOContext *pb = s->pb;
+ AVStream *st;
+ unsigned int audio_subsegments;
+
+ avio_skip(pb, 3);
+ mtv->file_size = avio_rl32(pb);
+ mtv->segments = avio_rl32(pb);
+ avio_skip(pb, 32);
+ mtv->audio_identifier = avio_rl24(pb);
+ mtv->audio_br = avio_rl16(pb);
+ mtv->img_colorfmt = avio_rl24(pb);
+ mtv->img_bpp = avio_r8(pb);
+ mtv->img_width = avio_rl16(pb);
+ mtv->img_height = avio_rl16(pb);
+ mtv->img_segment_size = avio_rl16(pb);
+
+ /* Calculate width and height if missing from header */
+
+ if(!mtv->img_width)
+ mtv->img_width=mtv->img_segment_size / (mtv->img_bpp>>3)
+ / mtv->img_height;
+
+ if(!mtv->img_height)
+ mtv->img_height=mtv->img_segment_size / (mtv->img_bpp>>3)
+ / mtv->img_width;
+
+ avio_skip(pb, 4);
+ audio_subsegments = avio_rl16(pb);
+
+ if (audio_subsegments == 0) {
+ avpriv_request_sample(s, "MTV files without audio");
+ return AVERROR_PATCHWELCOME;
+ }
- /* first packet is always audio*/
+ mtv->full_segment_size =
+ audio_subsegments * (MTV_AUDIO_PADDING_SIZE + MTV_ASUBCHUNK_DATA_SIZE) +
+ mtv->img_segment_size;
+ mtv->video_fps = (mtv->audio_br / 4) / audio_subsegments;
- mtv->audio_packet_count = 1;
+ // FIXME Add sanity check here
- /* all systems go! init decoders */
+ // all systems go! init decoders
- /* video - raw rgb565 */
+ // video - raw rgb565
- st = av_new_stream(s, VIDEO_SID);
+ st = avformat_new_stream(s, NULL);
if(!st)
return AVERROR(ENOMEM);
- av_set_pts_info(st, 64, 1, mtv->video_fps);
- st->codec->codec_type = CODEC_TYPE_VIDEO;
- st->codec->codec_id = CODEC_ID_RAWVIDEO;
- st->codec->codec_tag = MKTAG('R', 'G', 'B', mtv->img_bpp);
+ avpriv_set_pts_info(st, 64, 1, mtv->video_fps);
+ st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
+ st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
+ st->codec->pix_fmt = AV_PIX_FMT_RGB565BE;
st->codec->width = mtv->img_width;
st->codec->height = mtv->img_height;
- st->codec->bits_per_sample = mtv->img_bpp;
st->codec->sample_rate = mtv->video_fps;
+ st->codec->extradata = av_strdup("BottomUp");
+ st->codec->extradata_size = 9;
- /* audio - mp3 */
+ // audio - mp3
- st = av_new_stream(s, AUDIO_SID);
+ st = avformat_new_stream(s, NULL);
if(!st)
return AVERROR(ENOMEM);
- av_set_pts_info(st, 64, 1, AUDIO_SAMPLING_RATE);
- st->codec->codec_type = CODEC_TYPE_AUDIO;
- st->codec->codec_id = CODEC_ID_MP3;
+ avpriv_set_pts_info(st, 64, 1, AUDIO_SAMPLING_RATE);
+ st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
+ st->codec->codec_id = AV_CODEC_ID_MP3;
st->codec->bit_rate = mtv->audio_br;
st->need_parsing = AVSTREAM_PARSE_FULL;
- /* Jump over header */
+ // Jump over header
- if(url_fseek(pb, MTV_HEADER_SIZE, SEEK_SET) != MTV_HEADER_SIZE)
+ if(avio_seek(pb, MTV_HEADER_SIZE, SEEK_SET) != MTV_HEADER_SIZE)
return AVERROR(EIO);
return 0;
static int mtv_read_packet(AVFormatContext *s, AVPacket *pkt)
{
MTVDemuxContext *mtv = s->priv_data;
- ByteIOContext *pb = s->pb;
+ AVIOContext *pb = s->pb;
int ret;
-#ifndef WORDS_BIGENDIAN
- int i;
-#endif
-
- ret = 0;
- if(mtv->audio_subsegments >= mtv->audio_packet_count)
+ if((avio_tell(pb) - s->data_offset + mtv->img_segment_size) % mtv->full_segment_size)
{
- url_fskip(pb, MTV_AUDIO_PADDING_SIZE);
+ avio_skip(pb, MTV_AUDIO_PADDING_SIZE);
ret = av_get_packet(pb, pkt, MTV_ASUBCHUNK_DATA_SIZE);
- if(ret != MTV_ASUBCHUNK_DATA_SIZE)
- return AVERROR(EIO);
+ if(ret < 0)
+ return ret;
- mtv->audio_packet_count++;
pkt->pos -= MTV_AUDIO_PADDING_SIZE;
- pkt->stream_index = AUDIO_SID;
+ pkt->stream_index = 1;
}else
{
ret = av_get_packet(pb, pkt, mtv->img_segment_size);
- if(ret != mtv->img_segment_size)
- return AVERROR(EIO);
-
-#ifndef WORDS_BIGENDIAN
-
- /* pkt->data is GGGRRRR BBBBBGGG
- * and we need RRRRRGGG GGGBBBBB
- * for PIX_FMT_RGB565 so here we
- * just swap bytes as they come
- */
-
- for(i=0;i<mtv->img_segment_size/2;i++)
- *((uint16_t *)pkt->data+i) = bswap_16(*((uint16_t *)pkt->data+i));
-#endif
- mtv->audio_packet_count = 1;
- pkt->stream_index = VIDEO_SID;
+ if(ret < 0)
+ return ret;
+
+ pkt->stream_index = 0;
}
return ret;
}
-AVInputFormat mtv_demuxer = {
- "MTV",
- NULL_IF_CONFIG_SMALL("MTV format"),
- sizeof(MTVDemuxContext),
- mtv_probe,
- mtv_read_header,
- mtv_read_packet,
+AVInputFormat ff_mtv_demuxer = {
+ .name = "mtv",
+ .long_name = NULL_IF_CONFIG_SMALL("MTV"),
+ .priv_data_size = sizeof(MTVDemuxContext),
+ .read_probe = mtv_probe,
+ .read_header = mtv_read_header,
+ .read_packet = mtv_read_packet,
};