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////////// Codec-specific routines used to interface between "MPlayer"
////////// and the "LIVE.COM Streaming Media" libraries:
#include "demux_rtp_internal.h"
extern "C" {
#include "stheader.h"
}
static void
needVideoFrameRate(demuxer_t* demuxer, MediaSubsession* subsession); // forward
static Boolean
parseQTState_video(QuickTimeGenericRTPSource::QTState const& qtState,
unsigned& fourcc); // forward
static Boolean
parseQTState_audio(QuickTimeGenericRTPSource::QTState const& qtState,
unsigned& fourcc, unsigned& numChannels); // forward
void rtpCodecInitialize_video(demuxer_t* demuxer,
MediaSubsession* subsession,
unsigned& flags) {
flags = 0;
// Create a dummy video stream header
// to make the main MPlayer code happy:
sh_video_t* sh_video = new_sh_video(demuxer,0);
BITMAPINFOHEADER* bih
= (BITMAPINFOHEADER*)calloc(1,sizeof(BITMAPINFOHEADER));
bih->biSize = sizeof(BITMAPINFOHEADER);
sh_video->bih = bih;
demux_stream_t* d_video = demuxer->video;
d_video->sh = sh_video; sh_video->ds = d_video;
// Map known video MIME types to the BITMAPINFOHEADER parameters
// that this program uses. (Note that not all types need all
// of the parameters to be set.)
if (strcmp(subsession->codecName(), "MPV") == 0 ||
strcmp(subsession->codecName(), "MP1S") == 0 ||
strcmp(subsession->codecName(), "MP2T") == 0) {
flags |= RTPSTATE_IS_MPEG12_VIDEO;
} else if (strcmp(subsession->codecName(), "H263") == 0 ||
strcmp(subsession->codecName(), "H263-1998") == 0) {
bih->biCompression = sh_video->format
= mmioFOURCC('H','2','6','3');
needVideoFrameRate(demuxer, subsession);
} else if (strcmp(subsession->codecName(), "H261") == 0) {
bih->biCompression = sh_video->format
= mmioFOURCC('H','2','6','1');
needVideoFrameRate(demuxer, subsession);
} else if (strcmp(subsession->codecName(), "JPEG") == 0) {
bih->biCompression = sh_video->format
= mmioFOURCC('M','J','P','G');
needVideoFrameRate(demuxer, subsession);
} else if (strcmp(subsession->codecName(), "MP4V-ES") == 0) {
bih->biCompression = sh_video->format
= mmioFOURCC('m','p','4','v');
// For the codec to work correctly, it may need a 'VOL Header' to be
// inserted at the front of the data stream. Construct this from the
// "config" MIME parameter, which was present (hopefully) in the
// session's SDP description:
unsigned configLen;
unsigned char* configData
= parseGeneralConfigStr(subsession->fmtp_config(), configLen);
insertRTPData(demuxer, demuxer->video, configData, configLen);
needVideoFrameRate(demuxer, subsession);
} else if (strcmp(subsession->codecName(), "X-QT") == 0 ||
strcmp(subsession->codecName(), "X-QUICKTIME") == 0) {
// QuickTime generic RTP format, as described in
// http://developer.apple.com/quicktime/icefloe/dispatch026.html
// We can't initialize this stream until we've received the first packet
// that has QuickTime "sdAtom" information in the header. So, keep
// reading packets until we get one:
unsigned char* packetData; unsigned packetDataLen; float pts;
QuickTimeGenericRTPSource* qtRTPSource
= (QuickTimeGenericRTPSource*)(subsession->rtpSource());
unsigned fourcc;
do {
if (!awaitRTPPacket(demuxer, demuxer->video,
packetData, packetDataLen, pts)) {
return;
}
} while (!parseQTState_video(qtRTPSource->qtState, fourcc));
bih->biCompression = sh_video->format = fourcc;
} else {
fprintf(stderr,
"Unknown MPlayer format code for MIME type \"video/%s\"\n",
subsession->codecName());
}
}
void rtpCodecInitialize_audio(demuxer_t* demuxer,
MediaSubsession* subsession,
unsigned& flags) {
flags = 0;
// Create a dummy audio stream header
// to make the main MPlayer code happy:
sh_audio_t* sh_audio = new_sh_audio(demuxer,0);
WAVEFORMATEX* wf = (WAVEFORMATEX*)calloc(1,sizeof(WAVEFORMATEX));
sh_audio->wf = wf;
demux_stream_t* d_audio = demuxer->audio;
d_audio->sh = sh_audio; sh_audio->ds = d_audio;
wf->nChannels = subsession->numChannels();
// Map known audio MIME types to the WAVEFORMATEX parameters
// that this program uses. (Note that not all types need all
// of the parameters to be set.)
wf->nSamplesPerSec
= subsession->rtpSource()->timestampFrequency(); // by default
if (strcmp(subsession->codecName(), "MPA") == 0 ||
strcmp(subsession->codecName(), "MPA-ROBUST") == 0 ||
strcmp(subsession->codecName(), "X-MP3-DRAFT-00") == 0) {
wf->wFormatTag = sh_audio->format = 0x55;
// Note: 0x55 is for layer III, but should work for I,II also
wf->nSamplesPerSec = 0; // sample rate is deduced from the data
} else if (strcmp(subsession->codecName(), "AC3") == 0) {
wf->wFormatTag = sh_audio->format = 0x2000;
wf->nSamplesPerSec = 0; // sample rate is deduced from the data
} else if (strcmp(subsession->codecName(), "PCMU") == 0) {
wf->wFormatTag = sh_audio->format = 0x7;
wf->nAvgBytesPerSec = 8000;
wf->nBlockAlign = 1;
wf->wBitsPerSample = 8;
wf->cbSize = 0;
} else if (strcmp(subsession->codecName(), "PCMA") == 0) {
wf->wFormatTag = sh_audio->format = 0x6;
wf->nAvgBytesPerSec = 8000;
wf->nBlockAlign = 1;
wf->wBitsPerSample = 8;
wf->cbSize = 0;
} else if (strcmp(subsession->codecName(), "GSM") == 0) {
wf->wFormatTag = sh_audio->format = mmioFOURCC('a','g','s','m');
wf->nAvgBytesPerSec = 1650;
wf->nBlockAlign = 33;
wf->wBitsPerSample = 16;
wf->cbSize = 0;
} else if (strcmp(subsession->codecName(), "QCELP") == 0) {
wf->wFormatTag = sh_audio->format = mmioFOURCC('Q','c','l','p');
wf->nAvgBytesPerSec = 1750;
wf->nBlockAlign = 35;
wf->wBitsPerSample = 16;
wf->cbSize = 0;
} else if (strcmp(subsession->codecName(), "MP4A-LATM") == 0) {
wf->wFormatTag = sh_audio->format = mmioFOURCC('m','p','4','a');
// For the codec to work correctly, it needs "AudioSpecificConfig"
// data, which is parsed from the "StreamMuxConfig" string that
// was present (hopefully) in the SDP description:
unsigned codecdata_len;
sh_audio->codecdata
= parseStreamMuxConfigStr(subsession->fmtp_config(),
codecdata_len);
sh_audio->codecdata_len = codecdata_len;
} else if (strcmp(subsession->codecName(), "MPEG4-GENERIC") == 0) {
wf->wFormatTag = sh_audio->format = mmioFOURCC('m','p','4','a');
// For the codec to work correctly, it needs "AudioSpecificConfig"
// data, which was present (hopefully) in the SDP description:
unsigned codecdata_len;
sh_audio->codecdata
= parseGeneralConfigStr(subsession->fmtp_config(),
codecdata_len);
sh_audio->codecdata_len = codecdata_len;
} else if (strcmp(subsession->codecName(), "X-QT") == 0 ||
strcmp(subsession->codecName(), "X-QUICKTIME") == 0) {
// QuickTime generic RTP format, as described in
// http://developer.apple.com/quicktime/icefloe/dispatch026.html
// We can't initialize this stream until we've received the first packet
// that has QuickTime "sdAtom" information in the header. So, keep
// reading packets until we get one:
unsigned char* packetData; unsigned packetDataLen; float pts;
QuickTimeGenericRTPSource* qtRTPSource
= (QuickTimeGenericRTPSource*)(subsession->rtpSource());
unsigned fourcc, numChannels;
do {
if (!awaitRTPPacket(demuxer, demuxer->audio,
packetData, packetDataLen, pts)) {
return;
}
} while (!parseQTState_audio(qtRTPSource->qtState, fourcc, numChannels));
wf->wFormatTag = sh_audio->format = fourcc;
wf->nChannels = numChannels;
} else {
fprintf(stderr,
"Unknown MPlayer format code for MIME type \"audio/%s\"\n",
subsession->codecName());
}
}
static void needVideoFrameRate(demuxer_t* demuxer,
MediaSubsession* subsession) {
// For some codecs, MPlayer's decoding software can't (or refuses to :-)
// figure out the frame rate by itself, so (unless the user specifies
// it manually, using "-fps") we figure it out ourselves here, using the
// presentation timestamps in successive packets,
extern float force_fps; if (force_fps != 0.0) return; // user used "-fps"
demux_stream_t* d_video = demuxer->video;
sh_video_t* sh_video = (sh_video_t*)(d_video->sh);
// If we already know the subsession's video frame rate, use it:
int fps = (int)(subsession->videoFPS());
if (fps != 0) {
sh_video->fps = fps;
return;
}
// Keep looking at incoming frames until we see two with different,
// non-zero "pts" timestamps:
unsigned char* packetData; unsigned packetDataLen;
float lastPTS = 0.0, curPTS;
unsigned const maxNumFramesToWaitFor = 100;
for (unsigned i = 0; i < maxNumFramesToWaitFor; ++i) {
if (!awaitRTPPacket(demuxer, d_video, packetData, packetDataLen, curPTS)) {
break;
}
if (curPTS > lastPTS && lastPTS != 0.0) {
// Use the difference between these two "pts"s to guess the frame rate.
// (should really check that there were no missing frames inbetween)#####
// Guess the frame rate as an integer. If it's not, use "-fps" instead.
fps = (int)(1/(curPTS-lastPTS) + 0.5); // rounding
fprintf(stderr, "demux_rtp: Guessed the video frame rate as %d frames-per-second.\n\t(If this is wrong, use the \"-fps <frame-rate>\" option instead.)\n", fps);
sh_video->fps = fps;
return;
}
lastPTS = curPTS;
}
fprintf(stderr, "demux_rtp: Failed to guess the video frame rate\n");
}
static Boolean
parseQTState_video(QuickTimeGenericRTPSource::QTState const& qtState,
unsigned& fourcc) {
// qtState's "sdAtom" field is supposed to contain a QuickTime video
// 'sample description' atom. This atom's name is the 'fourcc' that we want:
char const* sdAtom = qtState.sdAtom;
if (sdAtom == NULL || qtState.sdAtomSize < 2*4) return False;
fourcc = *(unsigned*)(&sdAtom[4]); // put in host order
return True;
}
static Boolean
parseQTState_audio(QuickTimeGenericRTPSource::QTState const& qtState,
unsigned& fourcc, unsigned& numChannels) {
// qtState's "sdAtom" field is supposed to contain a QuickTime audio
// 'sample description' atom. This atom's name is the 'fourcc' that we want.
// Also, the top half of the 5th word following the atom name should
// contain the number of channels ("numChannels") that we want:
char const* sdAtom = qtState.sdAtom;
if (sdAtom == NULL || qtState.sdAtomSize < 7*4) return False;
fourcc = *(unsigned*)(&sdAtom[4]); // put in host order
char const* word7Ptr = &sdAtom[6*4];
numChannels = (word7Ptr[0]<<8)|(word7Ptr[1]);
return True;
}
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