mpv/libmpdemux/demux_roq.c

254 lines
7.7 KiB
C

/*
RoQ file demuxer for the MPlayer program
by Mike Melanson
based on Dr. Tim Ferguson's RoQ document found at:
http://www.csse.monash.edu.au/~timf/videocodec.html
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"
#include "stream.h"
#include "demuxer.h"
#include "stheader.h"
#define RoQ_INFO 0x1001
#define RoQ_QUAD_CODEBOOK 0x1002
#define RoQ_QUAD_VQ 0x1011
#define RoQ_SOUND_MONO 0x1020
#define RoQ_SOUND_STEREO 0x1021
#define CHUNK_TYPE_AUDIO 0
#define CHUNK_TYPE_VIDEO 1
typedef struct roq_chunk_t
{
int chunk_type;
off_t chunk_offset;
int chunk_size;
float video_chunk_number; // in the case of a video chunk
int running_audio_sample_count; // for an audio chunk
} roq_chunk_t;
typedef struct roq_data_t
{
int total_chunks;
int current_chunk;
int total_video_chunks;
int total_audio_sample_count;
roq_chunk_t *chunks;
} roq_data_t;
// Check if a stream qualifies as a RoQ file based on the magic numbers
// at the start of the file:
// 84 10 FF FF FF FF xx xx
int roq_check_file(demuxer_t *demuxer)
{
stream_reset(demuxer->stream);
stream_seek(demuxer->stream, 0);
if ((stream_read_dword(demuxer->stream) == 0x8410FFFF) &&
((stream_read_dword(demuxer->stream) & 0xFFFF0000) == 0xFFFF0000))
return 1;
else
return 0;
}
// return value:
// 0 = EOF or no stream found
// 1 = successfully read a packet
int demux_roq_fill_buffer(demuxer_t *demuxer)
{
sh_video_t *sh_video = demuxer->video->sh;
roq_data_t *roq_data = (roq_data_t *)demuxer->priv;
roq_chunk_t roq_chunk;
if (roq_data->current_chunk >= roq_data->total_chunks)
return 0;
roq_chunk = roq_data->chunks[roq_data->current_chunk];
// make sure we're at the right place in the stream and fetch the chunk
stream_seek(demuxer->stream, roq_chunk.chunk_offset);
if (roq_chunk.chunk_type == CHUNK_TYPE_AUDIO)
ds_read_packet(demuxer->audio, demuxer->stream, roq_chunk.chunk_size,
0,
roq_chunk.chunk_offset, 0);
else
ds_read_packet(demuxer->video, demuxer->stream, roq_chunk.chunk_size,
roq_chunk.video_chunk_number / sh_video->fps,
roq_chunk.chunk_offset, 0);
roq_data->current_chunk++;
return 1;
}
demuxer_t* demux_open_roq(demuxer_t* demuxer)
{
sh_video_t *sh_video = NULL;
sh_audio_t *sh_audio = NULL;
roq_data_t *roq_data = (roq_data_t *)malloc(sizeof(roq_data_t));
int chunk_id;
int chunk_size;
int chunk_arg;
int last_chunk_id = 0;
int largest_audio_chunk = 0;
int fps;
roq_data->total_chunks = 0;
roq_data->current_chunk = 0;
roq_data->total_video_chunks = 0;
roq_data->chunks = NULL;
// position the stream and start traversing
stream_seek(demuxer->stream, 6);
fps = stream_read_word_le(demuxer->stream);
while (!stream_eof(demuxer->stream))
{
chunk_id = stream_read_word_le(demuxer->stream);
chunk_size = stream_read_dword_le(demuxer->stream);
chunk_arg = stream_read_word_le(demuxer->stream);
// this is the only useful header info in the file
if (chunk_id == RoQ_INFO)
{
// there should only be one RoQ_INFO chunk per file
if (sh_video)
{
mp_msg(MSGT_DECVIDEO, MSGL_WARN, "Found more than one RoQ_INFO chunk\n");
stream_skip(demuxer->stream, 8);
}
else
{
// this is a good opportunity to create a video stream header
sh_video = new_sh_video(demuxer, 0);
// make sure the demuxer knows about the new stream header
demuxer->video->sh = sh_video;
// make sure that the video demuxer stream header knows about its
// parent video demuxer stream
sh_video->ds = demuxer->video;
sh_video->disp_w = stream_read_word_le(demuxer->stream);
sh_video->disp_h = stream_read_word_le(demuxer->stream);
stream_skip(demuxer->stream, 4);
// custom fourcc for internal MPlayer use
sh_video->format = mmioFOURCC('R', 'o', 'Q', 'V');
// constant frame rate
sh_video->fps = fps;
sh_video->frametime = 1 / sh_video->fps;
}
}
else if ((chunk_id == RoQ_SOUND_MONO) ||
(chunk_id == RoQ_SOUND_STEREO))
{
// create the audio stream header if it hasn't been created it
if (sh_audio == NULL)
{
// make the header first
sh_audio = new_sh_audio(demuxer, 0);
// make sure the demuxer knows about the new stream header
demuxer->audio->sh = sh_audio;
// make sure that the audio demuxer stream header knows about its
// parent audio demuxer stream
sh_audio->ds = demuxer->audio;
// go through the bother of making a WAVEFORMATEX structure
sh_audio->wf = (WAVEFORMATEX *)malloc(sizeof(WAVEFORMATEX));
// custom fourcc for internal MPlayer use
sh_audio->format = mmioFOURCC('R', 'o', 'Q', 'A');
if (chunk_id == RoQ_SOUND_STEREO)
sh_audio->wf->nChannels = 2;
else
sh_audio->wf->nChannels = 1;
// always 22KHz, 16-bit
sh_audio->wf->nSamplesPerSec = 22050;
sh_audio->wf->wBitsPerSample = 16;
}
// index the chunk
roq_data->chunks = (roq_chunk_t *)realloc(roq_data->chunks,
(roq_data->total_chunks + 1) * sizeof (roq_chunk_t));
roq_data->chunks[roq_data->total_chunks].chunk_type = CHUNK_TYPE_AUDIO;
roq_data->chunks[roq_data->total_chunks].chunk_offset =
stream_tell(demuxer->stream) - 8;
roq_data->chunks[roq_data->total_chunks].chunk_size = chunk_size + 8;
roq_data->chunks[roq_data->total_chunks].running_audio_sample_count =
roq_data->total_audio_sample_count;
// audio housekeeping
if (chunk_size > largest_audio_chunk)
largest_audio_chunk = chunk_size;
roq_data->total_audio_sample_count +=
(chunk_size / sh_audio->wf->nChannels);
stream_skip(demuxer->stream, chunk_size);
roq_data->total_chunks++;
}
else if ((chunk_id == RoQ_QUAD_CODEBOOK) ||
((chunk_id == RoQ_QUAD_VQ) && (last_chunk_id != RoQ_QUAD_CODEBOOK)))
{
// index a new chunk if it's a codebook or quad VQ not following a
// codebook
roq_data->chunks = (roq_chunk_t *)realloc(roq_data->chunks,
(roq_data->total_chunks + 1) * sizeof (roq_chunk_t));
roq_data->chunks[roq_data->total_chunks].chunk_type = CHUNK_TYPE_VIDEO;
roq_data->chunks[roq_data->total_chunks].chunk_offset =
stream_tell(demuxer->stream) - 8;
roq_data->chunks[roq_data->total_chunks].chunk_size = chunk_size + 8;
roq_data->chunks[roq_data->total_chunks].video_chunk_number =
roq_data->total_video_chunks++;
stream_skip(demuxer->stream, chunk_size);
roq_data->total_chunks++;
}
else if ((chunk_id == RoQ_QUAD_VQ) && (last_chunk_id == RoQ_QUAD_CODEBOOK))
{
// if it's a quad VQ chunk following a codebook chunk, extend the last
// chunk
roq_data->chunks[roq_data->total_chunks - 1].chunk_size += (chunk_size + 8);
stream_skip(demuxer->stream, chunk_size);
}
else if (!stream_eof(demuxer->stream))
{
mp_msg(MSGT_DECVIDEO, MSGL_WARN, "Unknown RoQ chunk ID: %04X\n", chunk_id);
}
last_chunk_id = chunk_id;
}
// minimum output buffer size = largest audio chunk * 2, since each byte
// in the DPCM encoding effectively represents 1 16-bit sample
// (store it in wf->nBlockAlign for the time being since init_audio() will
// step on it anyway)
if (sh_audio)
sh_audio->wf->nBlockAlign = largest_audio_chunk * 2;
roq_data->current_chunk = 0;
demuxer->priv = roq_data;
stream_reset(demuxer->stream);
return demuxer;
}
void demux_close_roq(demuxer_t* demuxer) {
roq_data_t *roq_data = demuxer->priv;
if(!roq_data)
return;
free(roq_data);
}