/*
* Guess the true sample aspect ratio of a video stream,
* given the MPEG aspect ratio code and the actual frame size
* (and the MPEG version, 1 or 2).
*
* Returns y4m_sar_UNKNOWN if it has no good guess.
*
*/
y4m_ratio_t
mpeg_guess_sample_aspect_ratio(int mpeg_version,
mpeg_aspect_code_t code,
int frame_width, int frame_height)
{
switch (mpeg_version)
{
case 1:
/* MPEG-1 codes turn into SAR's, just not quite the right ones.
For the common/known values, we provide the ratio used in practice,
otherwise say we don't know.*/
switch (code)
{
case 1: return y4m_sar_SQUARE; break;
case 3: return y4m_sar_PAL_16_9; break;
case 6: return y4m_sar_NTSC_16_9; break;
case 8: return y4m_sar_PAL_CCIR601; break;
case 12: return y4m_sar_NTSC_CCIR601; break;
default:
return y4m_sar_UNKNOWN; break;
}
break;
case 2:
/* MPEG-2 codes turn into Display Aspect Ratios, though not exactly the
DAR's used in practice. For common/standard frame sizes, we provide
the original SAR; otherwise, we say we don't know. */
if (code == 1)
{
return y4m_sar_SQUARE; /* '1' means square *pixels* in MPEG-2 */
}
else if ((code >= 2) && (code <= 4))
{
return y4m_guess_sar(frame_width, frame_height,
mpeg2_aspect_ratios[code]);
}
else
{
return y4m_sar_UNKNOWN;
}
break;
default:
return y4m_sar_UNKNOWN;
break;
}
}
static int tc_y4m_open_video(Y4MPrivateData *pd, const char *filename,
vob_t *vob)
{
int asr, ret;
y4m_ratio_t framerate;
y4m_ratio_t asr_rate;
/* avoid fd loss in case of failed configuration */
if (pd->fd_vid == -1) {
pd->fd_vid = open(filename,
O_RDWR|O_CREAT|O_TRUNC,
S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH);
if (pd->fd_vid == -1) {
tc_log_error(MOD_NAME, "failed to open video stream file '%s'"
" (reason: %s)", filename,
strerror(errno));
return TC_ERROR;
}
}
y4m_init_stream_info(&(pd->streaminfo));
//note: this is the real framerate of the raw stream
framerate = (vob->ex_frc == 0) ?mpeg_conform_framerate(vob->ex_fps)
:mpeg_framerate(vob->ex_frc);
if (framerate.n == 0 && framerate.d == 0) {
framerate.n = vob->ex_fps * 1000;
framerate.d = 1000;
}
asr = (vob->ex_asr < 0) ?vob->im_asr :vob->ex_asr;
tc_asr_code_to_ratio(asr, &asr_rate.n, &asr_rate.d);
y4m_init_stream_info(&(pd->streaminfo));
y4m_si_set_framerate(&(pd->streaminfo), framerate);
if (vob->encode_fields == TC_ENCODE_FIELDS_TOP_FIRST) {
y4m_si_set_interlace(&(pd->streaminfo), Y4M_ILACE_TOP_FIRST);
} else if (vob->encode_fields == TC_ENCODE_FIELDS_BOTTOM_FIRST) {
y4m_si_set_interlace(&(pd->streaminfo), Y4M_ILACE_BOTTOM_FIRST);
} else if (vob->encode_fields == TC_ENCODE_FIELDS_PROGRESSIVE) {
y4m_si_set_interlace(&(pd->streaminfo), Y4M_ILACE_NONE);
}
/* XXX */
y4m_si_set_sampleaspect(&(pd->streaminfo),
y4m_guess_sar(pd->width,
pd->height,
asr_rate));
y4m_si_set_height(&(pd->streaminfo), pd->height);
y4m_si_set_width(&(pd->streaminfo), pd->width);
/* Y4M_CHROMA_420JPEG 4:2:0, H/V centered, for JPEG/MPEG-1 */
/* Y4M_CHROMA_420MPEG2 4:2:0, H cosited, for MPEG-2 */
/* Y4M_CHROMA_420PALDV 4:2:0, alternating Cb/Cr, for PAL-DV */
y4m_si_set_chroma(&(pd->streaminfo), Y4M_CHROMA_420JPEG); // XXX
ret = y4m_write_stream_header(pd->fd_vid, &(pd->streaminfo));
if (ret != Y4M_OK) {
tc_log_warn(MOD_NAME, "failed to write video YUV4MPEG2 header: %s",
y4m_strerr(ret));
return TC_ERROR;
}
return TC_OK;
}
void writeoutYUV4MPEGheader(int out_fd,
LavParam *param,
EditList el,
y4m_stream_info_t *streaminfo)
{
int n;
y4m_si_set_width(streaminfo, param->output_width);
y4m_si_set_height(streaminfo, param->output_height);
y4m_si_set_interlace(streaminfo, param->interlace);
y4m_si_set_framerate(streaminfo, mpeg_conform_framerate(el.video_fps));
if (!Y4M_RATIO_EQL(param->sar, y4m_sar_UNKNOWN)) {
y4m_si_set_sampleaspect(streaminfo, param->sar);
} else if ((el.video_sar_width != 0) || (el.video_sar_height != 0)) {
y4m_ratio_t sar;
sar.n = el.video_sar_width;
sar.d = el.video_sar_height;
y4m_si_set_sampleaspect(streaminfo, sar);
} else {
/* no idea! ...eh, just guess. */
mjpeg_warn("unspecified sample-aspect-ratio --- taking a guess...");
y4m_si_set_sampleaspect(streaminfo,
y4m_guess_sar(param->output_width,
param->output_height,
param->dar));
}
switch (el_video_frame_data_format(0, &el)) { /* FIXME: checking only 0-th frame. */
case DATAFORMAT_YUV420:
switch (param->chroma) {
case Y4M_UNKNOWN:
case Y4M_CHROMA_420JPEG:
break;
case Y4M_CHROMA_420MPEG2:
case Y4M_CHROMA_420PALDV:
mjpeg_warn("4:2:0 chroma should be '420jpeg' with this input");
break;
default:
mjpeg_error_exit1("must specify 4:2:0 chroma (should be '420jpeg') with this input");
break;
}
break;
case DATAFORMAT_YUV422:
switch (param->chroma) {
case Y4M_CHROMA_422:
break;
default:
mjpeg_error_exit1("must specify chroma '422' with this input");
break;
}
break;
case DATAFORMAT_DV2:
#ifndef HAVE_LIBDV
mjpeg_error_exit1("DV input was not configured at compile time");
#else
el_get_video_frame(jpeg_data, 0, &el); /* FIXME: checking only 0-th frame. */
dv_parse_header(decoder, jpeg_data);
switch(decoder->sampling) {
case e_dv_sample_420:
switch (param->chroma) {
case Y4M_UNKNOWN:
mjpeg_info("set chroma '420paldv' from input");
param->chroma = Y4M_CHROMA_420PALDV;
break;
case Y4M_CHROMA_420PALDV:
break;
case Y4M_CHROMA_420JPEG:
case Y4M_CHROMA_420MPEG2:
mjpeg_warn("4:2:0 chroma should be '420paldv' with this input");
break;
case Y4M_CHROMA_422:
if(libdv_pal_yv12 == 1 )
mjpeg_error_exit1("must specify 4:2:0 chroma (should be '420paldv') with this input");
break;
default:
mjpeg_error_exit1("must specify 4:2:0 chroma (should be '420paldv') with this input");
break;
}
break;
case e_dv_sample_411:
if (param->chroma != Y4M_CHROMA_411)
mjpeg_info("chroma '411' recommended with this input");
switch (param->chroma) {
case Y4M_CHROMA_420MPEG2:
case Y4M_CHROMA_420PALDV:
mjpeg_warn("4:2:0 chroma should be '420jpeg' with this input");
break;
}
break;
case e_dv_sample_422:
if (param->chroma != Y4M_CHROMA_422)
mjpeg_info("chroma '422' recommended with this input");
switch (param->chroma) {
case Y4M_CHROMA_420MPEG2:
case Y4M_CHROMA_420PALDV:
mjpeg_warn("4:2:0 chroma should be '420jpeg' with this input");
break;
}
break;
default:
break;
}
#endif
break;
case DATAFORMAT_MJPG:
if (param->chroma != Y4M_CHROMA_422 && el.chroma == Y4M_CHROMA_422)
mjpeg_info("chroma '422' recommended with this input");
switch (param->chroma) {
case Y4M_CHROMA_420MPEG2:
case Y4M_CHROMA_420PALDV:
mjpeg_warn("4:2:0 chroma should be '420jpeg' with this input");
break;
}
break;
}
if (param->chroma == Y4M_UNKNOWN) {
mjpeg_info("set default chroma '420jpeg'");
param->chroma = Y4M_CHROMA_420JPEG;
}
y4m_si_set_chroma(streaminfo, param->chroma);
n = y4m_write_stream_header(out_fd, streaminfo);
if (n != Y4M_OK)
mjpeg_error("Failed to write stream header: %s", y4m_strerr(n));
}
