yuv4mpeg.c

Motion JPEG编解码器源代码

  /* non-zero on error */
  return y4m_parse_frame_tags(line, si, fi);
}


int y4m_write_frame_header(int fd,
			   const y4m_stream_info_t *si,
			   const y4m_frame_info_t *fi)
{
  char s[Y4M_LINE_MAX+1];
  int n, err;

  if (si->interlace == Y4M_ILACE_MIXED) {
    if (_y4mparam_feature_level < 1) return Y4M_ERR_FEATURE;
    n = snprintf(s, sizeof(s), "%s I%c%c%c", Y4M_FRAME_MAGIC,
		 (fi->presentation == Y4M_PRESENT_TOP_FIRST)        ? 't' :
		 (fi->presentation == Y4M_PRESENT_TOP_FIRST_RPT)    ? 'T' :
		 (fi->presentation == Y4M_PRESENT_BOTTOM_FIRST)     ? 'b' :
		 (fi->presentation == Y4M_PRESENT_BOTTOM_FIRST_RPT) ? 'B' :
		 (fi->presentation == Y4M_PRESENT_PROG_SINGLE) ? '1' :
		 (fi->presentation == Y4M_PRESENT_PROG_DOUBLE) ? '2' :
		 (fi->presentation == Y4M_PRESENT_PROG_TRIPLE) ? '3' :
		 '?',
		 (fi->temporal == Y4M_SAMPLING_PROGRESSIVE) ? 'p' :
		 (fi->temporal == Y4M_SAMPLING_INTERLACED)  ? 'i' :
		 '?',
		 (fi->spatial == Y4M_SAMPLING_PROGRESSIVE) ? 'p' :
		 (fi->spatial == Y4M_SAMPLING_INTERLACED)  ? 'i' :
		 '?'
		 );
  } else {
    n = snprintf(s, sizeof(s), "%s", Y4M_FRAME_MAGIC);
  }
  
  if ((n < 0) || (n > Y4M_LINE_MAX)) return Y4M_ERR_HEADER;
  if ((err = y4m_snprint_xtags(s + n, sizeof(s) - n - 1, &(fi->x_tags))) 
      != Y4M_OK) 
    return err;
  /* non-zero on error */
  return (y4m_write(fd, s, strlen(s)) ? Y4M_ERR_SYSTEM : Y4M_OK);
}



/*************************************************************************
 *
 * Read/Write entire frame
 *
 *************************************************************************/

int y4m_read_frame_data(int fd, const y4m_stream_info_t *si, 
                        y4m_frame_info_t *fi, uint8_t * const *frame)
{
  int planes = y4m_si_get_plane_count(si);
  int p;
  
  /* Read each plane */
  for (p = 0; p < planes; p++) {
    int w = y4m_si_get_plane_width(si, p);
    int h = y4m_si_get_plane_height(si, p);
    if (y4m_read(fd, frame[p], w*h)) return Y4M_ERR_SYSTEM;
  }
  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_write_frame(int fd, const y4m_stream_info_t *si, 
		    const y4m_frame_info_t *fi, uint8_t * const *frame)
{
  int planes = y4m_si_get_plane_count(si);
  int err, p;

  /* Write frame header */
  if ((err = y4m_write_frame_header(fd, si, fi)) != Y4M_OK) return err;
  /* Write each plane */
  for (p = 0; p < planes; p++) {
    int w = y4m_si_get_plane_width(si, p);
    int h = y4m_si_get_plane_height(si, p);
    if (y4m_write(fd, frame[p], w*h)) return Y4M_ERR_SYSTEM;
  }
  return Y4M_OK;
}



/*************************************************************************
 *
 * Read/Write entire frame, (de)interleaved (to)from two separate fields
 *
 *************************************************************************/


int y4m_read_fields_data(int fd, const y4m_stream_info_t *si,
                         y4m_frame_info_t *fi,
                         uint8_t * const *upper_field, 
                         uint8_t * const *lower_field)
{
  int p;
  int planes = y4m_si_get_plane_count(si);
  const int maxrbuf=32*1024;
  uint8_t *rbuf=_y4m_alloc(maxrbuf);
  int rbufpos=0,rbuflen=0;
  
  /* Read each plane */
  for (p = 0; p < planes; p++) {
    uint8_t *dsttop = upper_field[p];
    uint8_t *dstbot = lower_field[p];
    int height = y4m_si_get_plane_height(si, p);
    int width = y4m_si_get_plane_width(si, p);
    int y;
    /* alternately read one line into each field */
    for (y = 0; y < height; y += 2) {
      if( width*2 >= maxrbuf ) {
        if (y4m_read(fd, dsttop, width)) goto y4merr;
        if (y4m_read(fd, dstbot, width)) goto y4merr;
      } else {
        if( rbufpos==rbuflen ) {
          rbuflen=(height-y)*width;
          if( rbuflen>maxrbuf )
            rbuflen=maxrbuf-maxrbuf%(2*width);
          if( y4m_read(fd,rbuf,rbuflen) )
            goto y4merr;
          rbufpos=0;
        }
            
        memcpy(dsttop,rbuf+rbufpos,width); rbufpos+=width;
        memcpy(dstbot,rbuf+rbufpos,width); rbufpos+=width;
      }
      dsttop+=width;
      dstbot+=width;
    }
  }
  _y4m_free(rbuf);
  return Y4M_OK;

 y4merr:
  _y4m_free(rbuf);
  return Y4M_ERR_SYSTEM;
}


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_write_fields(int fd, const y4m_stream_info_t *si,
		     const y4m_frame_info_t *fi,
		     uint8_t * const *upper_field, 
		     uint8_t * const *lower_field)
{
  int p, err;
  int planes = y4m_si_get_plane_count(si);
  int numwbuf=0;
  const int maxwbuf=32*1024;
  uint8_t *wbuf;
  
  /* Write frame header */
  if ((err = y4m_write_frame_header(fd, si, fi)) != Y4M_OK) return err;
  /* Write each plane */
  wbuf=_y4m_alloc(maxwbuf);
  for (p = 0; p < planes; p++) {
    uint8_t *srctop = upper_field[p];
    uint8_t *srcbot = lower_field[p];
    int height = y4m_si_get_plane_height(si, p);
    int width = y4m_si_get_plane_width(si, p);
    int y;
    /* alternately write one line from each field */
    for (y = 0; y < height; y += 2) {
      if( width*2 >= maxwbuf ) {
        if (y4m_write(fd, srctop, width)) goto y4merr;
        if (y4m_write(fd, srcbot, width)) goto y4merr;
      } else {
        if (numwbuf + 2 * width > maxwbuf) {
          if(y4m_write(fd, wbuf, numwbuf)) goto y4merr;
          numwbuf=0;
        }

        memcpy(wbuf+numwbuf,srctop,width); numwbuf += width;
        memcpy(wbuf+numwbuf,srcbot,width); numwbuf += width;
      }
      srctop  += width;
      srcbot  += width;
    }
  }
  if( numwbuf )
    if( y4m_write(fd, wbuf, numwbuf) )
      goto y4merr;
  _y4m_free(wbuf);
  return Y4M_OK;

 y4merr:
  _y4m_free(wbuf);
  return Y4M_ERR_SYSTEM;
}


/*************************************************************************
 *
 * Handy logging of stream info
 *
 *************************************************************************/

void y4m_log_stream_info(log_level_t level, const char *prefix,
			 const y4m_stream_info_t *i)
{
  char s[256];

  snprintf(s, sizeof(s), "  frame size:  ");
  if (i->width == Y4M_UNKNOWN)
    snprintf(s+strlen(s), sizeof(s)-strlen(s), "(?)x");
  else
    snprintf(s+strlen(s), sizeof(s)-strlen(s), "%dx", i->width);
  if (i->height == Y4M_UNKNOWN)
    snprintf(s+strlen(s), sizeof(s)-strlen(s), "(?) pixels ");
  else
    snprintf(s+strlen(s), sizeof(s)-strlen(s), "%d pixels ", i->height);
  {
    int framelength = y4m_si_get_framelength(i);
    if (framelength == Y4M_UNKNOWN)
      snprintf(s+strlen(s), sizeof(s)-strlen(s), "(? bytes)");
    else
      snprintf(s+strlen(s), sizeof(s)-strlen(s), "(%d bytes)", framelength);
    mjpeg_log(level, "%s%s", prefix, s);
  }
  {
    const char *desc = y4m_chroma_description(i->chroma);
    if (desc == NULL) desc = "unknown!";
    mjpeg_log(level, "%s      chroma:  %s", prefix, desc);
  }
  if ((i->framerate.n == 0) && (i->framerate.d == 0))
    mjpeg_log(level, "%s  frame rate:  ??? fps", prefix);
  else
    mjpeg_log(level, "%s  frame rate:  %d/%d fps (~%f)", prefix,
	      i->framerate.n, i->framerate.d, 
	      (double) i->framerate.n / (double) i->framerate.d);
  mjpeg_log(level, "%s   interlace:  %s", prefix,
	  (i->interlace == Y4M_ILACE_NONE) ? "none/progressive" :
	  (i->interlace == Y4M_ILACE_TOP_FIRST) ? "top-field-first" :
	  (i->interlace == Y4M_ILACE_BOTTOM_FIRST) ? "bottom-field-first" :
	  (i->interlace == Y4M_ILACE_MIXED) ? "mixed-mode" :
	  "anyone's guess");
  if ((i->sampleaspect.n == 0) && (i->sampleaspect.d == 0))
    mjpeg_log(level, "%ssample aspect ratio:  ?:?", prefix);
  else
    mjpeg_log(level, "%ssample aspect ratio:  %d:%d", prefix,
	      i->sampleaspect.n, i->sampleaspect.d);
}


/*************************************************************************
 *
 * Convert error code to string
 *
 *************************************************************************/

const char *y4m_strerr(int err)
{
  switch (err) {
  case Y4M_OK:          return "no error";
  case Y4M_ERR_RANGE:   return "parameter out of range";
  case Y4M_ERR_SYSTEM:  return "system error (failed read/write)";
  case Y4M_ERR_HEADER:  return "bad stream or frame header";
  case Y4M_ERR_BADTAG:  return "unknown header tag";
  case Y4M_ERR_MAGIC:   return "bad header magic";
  case Y4M_ERR_XXTAGS:  return "too many xtags";
  case Y4M_ERR_EOF:     return "end-of-file";
  case Y4M_ERR_BADEOF:  return "stream ended unexpectedly (EOF)";
  case Y4M_ERR_FEATURE: return "stream requires unsupported features";
  default: 
    return "unknown error code";
  }
}


/*************************************************************************
 *
 * Chroma subsampling stuff
 *
 *************************************************************************/

y4m_ratio_t y4m_chroma_ss_x_ratio(int chroma_mode)
{
  y4m_ratio_t r;
  switch (chroma_mode) {
  case Y4M_CHROMA_444ALPHA:
  case Y4M_CHROMA_444:
  case Y4M_CHROMA_MONO:
    r.n = 1; r.d = 1; break;
  case Y4M_CHROMA_420JPEG:
  case Y4M_CHROMA_420MPEG2:
  case Y4M_CHROMA_420PALDV:
  case Y4M_CHROMA_422:
    r.n = 1; r.d = 2; break;
  case Y4M_CHROMA_411:
    r.n = 1; r.d = 4; break;
  default:
    r.n = 0; r.d = 0;
  }
  return r;
}

y4m_ratio_t y4m_chroma_ss_y_ratio(int chroma_mode)
{
  y4m_ratio_t r;
  switch (chroma_mode) {
  case Y4M_CHROMA_444ALPHA:
  case Y4M_CHROMA_444:
  case Y4M_CHROMA_MONO:
  case Y4M_CHROMA_422:
  case Y4M_CHROMA_411:
    r.n = 1; r.d = 1; break;
  case Y4M_CHROMA_420JPEG:
  case Y4M_CHROMA_420MPEG2:
  case Y4M_CHROMA_420PALDV:
    r.n = 1; r.d = 2; break;
  default:
    r.n = 0; r.d = 0;
  }
  return r;
}


#if 0  /* unfinished work here */
y4m_ratio_t y4m_chroma_ss_x_offset(int chroma_mode, int field, int plane)
{
  y4m_ratio_t r;
  switch (chroma_mode) {
  case Y4M_CHROMA_444ALPHA:
  case Y4M_CHROMA_444:
  case Y4M_CHROMA_MONO:
  case Y4M_CHROMA_422:
  case Y4M_CHROMA_411:
    r.n = 0; r.d = 1; break;
  case Y4M_CHROMA_420JPEG:
  case Y4M_CHROMA_420MPEG2:
  case Y4M_CHROMA_420PALDV:
    r.n = 1; r.d = 2; break;
  default:
    r.n = 0; r.d = 0;
  }
  return r;
}

y4m_ratio_t y4m_chroma_ss_y_offset(int chroma_mode, int field, int plane);
{
  y4m_ratio_t r;
  switch (chroma_mode) {
  case Y4M_CHROMA_444ALPHA:
  case Y4M_CHROMA_444:
  case Y4M_CHROMA_MONO:
  case Y4M_CHROMA_422:
  case Y4M_CHROMA_411:
    r.n = 0; r.d = 1; break;
  case Y4M_CHROMA_420JPEG:
  case Y4M_CHROMA_420MPEG2:
  case Y4M_CHROMA_420PALDV:
    r.n = 1; r.d = 2; break;
  default:
    r.n = 0; r.d = 0;
  }
  return r;
}
#endif



int y4m_chroma_parse_keyword(const char *s)
{
  if (!strcasecmp("420jpeg", s))
    return Y4M_CHROMA_420JPEG;
  else if (!strcasecmp("420mpeg2", s))
    return Y4M_CHROMA_420MPEG2;
  else if (!strcasecmp("420paldv", s))
    return Y4M_CHROMA_420PALDV;
  else if (!strcasecmp("444", s))
    return Y4M_CHROMA_444;
  else if (!strcasecmp("422", s))
    return Y4M_CHROMA_422;
  else if (!strcasecmp("411", s))
    return Y4M_CHROMA_411;
  else if (!strcasecmp("mono", s))
    return Y4M_CHROMA_MONO;
  else if (!strcasecmp("444alpha", s))
    return Y4M_CHROMA_444ALPHA;
  else
    return Y4M_UNKNOWN;
}


const char *y4m_chroma_keyword(int chroma_mode)
{
  switch (chroma_mode) {
  case Y4M_CHROMA_420JPEG:  return "420jpeg";
  case Y4M_CHROMA_420MPEG2: return "420mpeg2";
  case Y4M_CHROMA_420PALDV: return "420paldv";
  case Y4M_CHROMA_444:      return "444";
  case Y4M_CHROMA_422:      return "422";
  case Y4M_CHROMA_411:      return "411";
  case Y4M_CHROMA_MONO:     return "mono";
  case Y4M_CHROMA_444ALPHA: return "444alpha";
  default:
    return NULL;
  }
}  


const char *y4m_chroma_description(int chroma_mode)
{           
  switch (chroma_mode) {
  case Y4M_CHROMA_420JPEG:  return "4:2:0 JPEG/MPEG-1 (interstitial)";
  case Y4M_CHROMA_420MPEG2: return "4:2:0 MPEG-2 (horiz. cositing)";
  case Y4M_CHROMA_420PALDV: return "4:2:0 PAL-DV (altern. siting)";
  case Y4M_CHROMA_444:      return "4:4:4 (no subsampling)";
  case Y4M_CHROMA_422:      return "4:2:2 (horiz. cositing)";
  case Y4M_CHROMA_411:      return "4:1:1 (horiz. cositing)";
  case Y4M_CHROMA_MONO:     return "luma plane only";
  case Y4M_CHROMA_444ALPHA: return "4:4:4 with alpha channel";
  default:
    return NULL;
  }
}