int y4m_read_fields(int fd, y4m_stream_info_t *si, y4m_frame_info_t *fi,
unsigned char *upper_field[3],
unsigned char *lower_field[3])
{
int i, y, err;
int width = si->width;
int height = si->height;
/* Read frame header */
if ((err = y4m_read_frame_header(fd, fi)) != Y4M_OK) return err;
/* Read Y', Cb, and Cr planes */
for (i = 0; i < 3; i++) {
unsigned char *srctop = upper_field[i];
unsigned char *srcbot = lower_field[i];
/* alternately write one line from each */
for (y = 0; y < height; y += 2) {
if (y4m_read(fd, srctop, width)) return Y4M_ERR_SYSTEM;
srctop += width;
if (y4m_read(fd, srcbot, width)) return Y4M_ERR_SYSTEM;
srcbot += width;
}
/* for chroma, width/height are half as big */
if (i == 0) {
width /= 2;
height /= 2;
}
}
return Y4M_OK;
}
static int internal_read_444_fields(int fd,
const y4m_stream_info_t *si,
y4m_frame_info_t *fi,
uint8_t * const upper_field[3],
uint8_t * const lower_field[3])
{
int i, y, err;
int width = y4m_si_get_width(si);
int height = y4m_si_get_height(si);
/* Read frame header */
if ((err = y4m_read_frame_header(fd, si, fi)) != Y4M_OK) return err;
/* Read Y', Cb, and Cr planes */
for (i = 0; i < 3; i++) {
uint8_t *srctop = upper_field[i];
uint8_t *srcbot = lower_field[i];
/* alternately write one line from each */
for (y = 0; y < height; y += 2) {
if (y4m_read(fd, srctop, width)) return Y4M_ERR_SYSTEM;
srctop += width;
if (y4m_read(fd, srcbot, width)) return Y4M_ERR_SYSTEM;
srcbot += width;
}
}
return Y4M_OK;
}
int y4m_read_frame(int fd, const y4m_stream_info_t *si,
y4m_frame_info_t *fi, uint8_t * const *frame)
{
int err;
/* Read frame header */
if ((err = y4m_read_frame_header(fd, si, fi)) != Y4M_OK) return err;
/* Read date */
return y4m_read_frame_data(fd, si, fi, frame);
}
int y4m_read_fields(int fd, const y4m_stream_info_t *si, y4m_frame_info_t *fi,
uint8_t * const *upper_field,
uint8_t * const *lower_field)
{
int err;
/* Read frame header */
if ((err = y4m_read_frame_header(fd, si, fi)) != Y4M_OK) return err;
/* Read data */
return y4m_read_fields_data(fd, si, fi, upper_field, lower_field);
}
int y4m_read_frame(stream_t *s, y4m_stream_info_t *si,
y4m_frame_info_t *fi, unsigned char *yuv[3])
{
int err;
int w = si->width;
int h = si->height;
/* Read frame header */
if ((err = y4m_read_frame_header(s, fi)) != Y4M_OK) return err;
/* Read luminance scanlines */
if (y4m_read(s, yuv[0], w*h)) return Y4M_ERR_SYSTEM;
/* Read chrominance scanlines */
if (y4m_read(s, yuv[1], w*h/4)) return Y4M_ERR_SYSTEM;
if (y4m_read(s, yuv[2], w*h/4)) return Y4M_ERR_SYSTEM;
return Y4M_OK;
}
static int internal_read_422_frame(int fd,
const y4m_stream_info_t *si,
y4m_frame_info_t *fi,
uint8_t * const yuv[3])
{
int err;
int w = y4m_si_get_width(si);
int h = y4m_si_get_height(si);
/* Read frame header */
if ((err = y4m_read_frame_header(fd, si, fi)) != Y4M_OK) return err;
/* Read luminance scanlines */
if (y4m_read(fd, yuv[0], w*h)) return Y4M_ERR_SYSTEM;
/* Read chrominance scanlines */
if (y4m_read(fd, yuv[1], w*h/2)) return Y4M_ERR_SYSTEM;
if (y4m_read(fd, yuv[2], w*h/2)) return Y4M_ERR_SYSTEM;
return Y4M_OK;
}
// Should probably just remove this...
int ysSource::read_frame_or_fields(int fdin, y4m_frame_info_t *frameinfo,
uint8_t **frame,
uint8_t **upper, uint8_t **lower)
{
int err;
err = y4m_read_frame_header(fdin, _stream.streaminfo(), frameinfo);
if (err != Y4M_OK) return err;
mjpeg_info("F-or-F: %d %d",
y4m_fi_get_temporal(frameinfo),
y4m_fi_get_spatial(frameinfo));
/* XXXXXX what about ip/pi/420 issues? XXXXXXX */
int sampling = y4m_fi_get_temporal(frameinfo);
if (sampling == Y4M_SAMPLING_PROGRESSIVE)
return y4m_read_frame_data(fdin, _stream.streaminfo(), frameinfo, frame);
else /* == Y4M_SAMPLING_INTERLACED */
return y4m_read_fields_data(fdin, _stream.streaminfo(), frameinfo,
upper, lower);
}
int ysSource::read_frame_header(int fdin, y4m_frame_info_t *frameinfo)
{
return y4m_read_frame_header(fdin, _stream.streaminfo(), frameinfo);
}
