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authorDavid Schleef <ds@schleef.org>2003-07-26 03:01:58 +0000
committerDavid Schleef <ds@schleef.org>2003-07-26 03:01:58 +0000
commit2f0cc8ec30e8c26fed7b2c9ac2614c9a7655fb65 (patch)
tree25c3fbda1c8f8f5a33cad05c78b40887be7d2fba /gst-libs/ext/mplex/yuv4mpeg.cc
parent4df5590ec318054389219b84153cce0ce363613b (diff)
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Moved from gst-plugins/ext/mplex/. See that directory for older changelogs.
Original commit message from CVS: Moved from gst-plugins/ext/mplex/. See that directory for older changelogs.
Diffstat (limited to 'gst-libs/ext/mplex/yuv4mpeg.cc')
-rw-r--r--gst-libs/ext/mplex/yuv4mpeg.cc880
1 files changed, 880 insertions, 0 deletions
diff --git a/gst-libs/ext/mplex/yuv4mpeg.cc b/gst-libs/ext/mplex/yuv4mpeg.cc
new file mode 100644
index 00000000..a9e1aebf
--- /dev/null
+++ b/gst-libs/ext/mplex/yuv4mpeg.cc
@@ -0,0 +1,880 @@
+/*
+ * yuv4mpeg.c: Functions for reading and writing "new" YUV4MPEG streams
+ *
+ * Copyright (C) 2001 Matthew J. Marjanovic <maddog@mir.com>
+ *
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ */
+
+#include <config.h>
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "yuv4mpeg.h"
+#include "yuv4mpeg_intern.h"
+#include "mjpeg_logging.h"
+
+
+static int _y4mparam_allow_unknown_tags = 1; /* default is forgiveness */
+
+static void *(*_y4m_alloc) (size_t bytes) = malloc;
+static void (*_y4m_free) (void *ptr) = free;
+
+
+
+int
+y4m_allow_unknown_tags (int yn)
+{
+ int old = _y4mparam_allow_unknown_tags;
+
+ if (yn >= 0)
+ _y4mparam_allow_unknown_tags = (yn) ? 1 : 0;
+ return old;
+}
+
+
+
+/*************************************************************************
+ *
+ * Convenience functions for fd read/write
+ *
+ * - guaranteed to transfer entire payload (or fail)
+ * - returns:
+ * 0 on complete success
+ * +(# of remaining bytes) on eof (for y4m_read)
+ * -(# of rem. bytes) on error (and ERRNO should be set)
+ *
+ *************************************************************************/
+
+
+ssize_t
+y4m_read (int fd, void *buf, size_t len)
+{
+ ssize_t n;
+ uint8_t *ptr = (uint8_t *) buf;
+
+ while (len > 0) {
+ n = read (fd, ptr, len);
+ if (n <= 0) {
+ /* return amount left to read */
+ if (n == 0)
+ return len; /* n == 0 --> eof */
+ else
+ return -len; /* n < 0 --> error */
+ }
+ ptr += n;
+ len -= n;
+ }
+ return 0;
+}
+
+
+ssize_t
+y4m_write (int fd, const void *buf, size_t len)
+{
+ ssize_t n;
+ const uint8_t *ptr = (const uint8_t *) buf;
+
+ while (len > 0) {
+ n = write (fd, ptr, len);
+ if (n <= 0)
+ return -len; /* return amount left to write */
+ ptr += n;
+ len -= n;
+ }
+ return 0;
+}
+
+
+
+/*************************************************************************
+ *
+ * "Extra tags" handling
+ *
+ *************************************************************************/
+
+
+static char *
+y4m_new_xtag (void)
+{
+ return (char *) _y4m_alloc (Y4M_MAX_XTAG_SIZE * sizeof (char));
+}
+
+
+void
+y4m_init_xtag_list (y4m_xtag_list_t * xtags)
+{
+ int i;
+
+ xtags->count = 0;
+ for (i = 0; i < Y4M_MAX_XTAGS; i++) {
+ xtags->tags[i] = NULL;
+ }
+}
+
+
+void
+y4m_fini_xtag_list (y4m_xtag_list_t * xtags)
+{
+ int i;
+
+ for (i = 0; i < Y4M_MAX_XTAGS; i++) {
+ if (xtags->tags[i] != NULL) {
+ _y4m_free (xtags->tags[i]);
+ xtags->tags[i] = NULL;
+ }
+ }
+ xtags->count = 0;
+}
+
+
+void
+y4m_copy_xtag_list (y4m_xtag_list_t * dest, const y4m_xtag_list_t * src)
+{
+ int i;
+
+ for (i = 0; i < src->count; i++) {
+ if (dest->tags[i] == NULL)
+ dest->tags[i] = y4m_new_xtag ();
+ strncpy (dest->tags[i], src->tags[i], Y4M_MAX_XTAG_SIZE);
+ }
+ dest->count = src->count;
+}
+
+
+
+static int
+y4m_snprint_xtags (char *s, int maxn, const y4m_xtag_list_t * xtags)
+{
+ int i, room;
+
+ for (i = 0, room = maxn - 1; i < xtags->count; i++) {
+ int n = snprintf (s, room + 1, " %s", xtags->tags[i]);
+
+ if ((n < 0) || (n > room))
+ return Y4M_ERR_HEADER;
+ s += n;
+ room -= n;
+ }
+ s[0] = '\n'; /* finish off header with newline */
+ s[1] = '\0'; /* ...and end-of-string */
+ return Y4M_OK;
+}
+
+
+int
+y4m_xtag_count (const y4m_xtag_list_t * xtags)
+{
+ return xtags->count;
+}
+
+
+const char *
+y4m_xtag_get (const y4m_xtag_list_t * xtags, int n)
+{
+ if (n >= xtags->count)
+ return NULL;
+ else
+ return xtags->tags[n];
+}
+
+
+int
+y4m_xtag_add (y4m_xtag_list_t * xtags, const char *tag)
+{
+ if (xtags->count >= Y4M_MAX_XTAGS)
+ return Y4M_ERR_XXTAGS;
+ if (xtags->tags[xtags->count] == NULL)
+ xtags->tags[xtags->count] = y4m_new_xtag ();
+ strncpy (xtags->tags[xtags->count], tag, Y4M_MAX_XTAG_SIZE);
+ (xtags->count)++;
+ return Y4M_OK;
+}
+
+
+int
+y4m_xtag_remove (y4m_xtag_list_t * xtags, int n)
+{
+ int i;
+ char *q;
+
+ if ((n < 0) || (n >= xtags->count))
+ return Y4M_ERR_RANGE;
+ q = xtags->tags[n];
+ for (i = n; i < (xtags->count - 1); i++)
+ xtags->tags[i] = xtags->tags[i + 1];
+ xtags->tags[i] = q;
+ (xtags->count)--;
+ return Y4M_OK;
+}
+
+
+int
+y4m_xtag_clearlist (y4m_xtag_list_t * xtags)
+{
+ xtags->count = 0;
+ return Y4M_OK;
+}
+
+
+int
+y4m_xtag_addlist (y4m_xtag_list_t * dest, const y4m_xtag_list_t * src)
+{
+ int i, j;
+
+ if ((dest->count + src->count) > Y4M_MAX_XTAGS)
+ return Y4M_ERR_XXTAGS;
+ for (i = dest->count, j = 0; j < src->count; i++, j++) {
+ if (dest->tags[i] == NULL)
+ dest->tags[i] = y4m_new_xtag ();
+ strncpy (dest->tags[i], src->tags[i], Y4M_MAX_XTAG_SIZE);
+ }
+ dest->count += src->count;
+ return Y4M_OK;
+}
+
+
+/*************************************************************************
+ *
+ * Creators/destructors for y4m_*_info_t structures
+ *
+ *************************************************************************/
+
+
+void
+y4m_init_stream_info (y4m_stream_info_t * info)
+{
+ if (info == NULL)
+ return;
+ /* initialize info */
+ info->width = Y4M_UNKNOWN;
+ info->height = Y4M_UNKNOWN;
+ info->interlace = Y4M_UNKNOWN;
+ info->framerate = y4m_fps_UNKNOWN;
+ info->sampleaspect = y4m_sar_UNKNOWN;
+ y4m_init_xtag_list (&(info->x_tags));
+}
+
+
+void
+y4m_copy_stream_info (y4m_stream_info_t * dest, const y4m_stream_info_t * src)
+{
+ if ((dest == NULL) || (src == NULL))
+ return;
+ /* copy info */
+ dest->width = src->width;
+ dest->height = src->height;
+ dest->interlace = src->interlace;
+ dest->framerate = src->framerate;
+ dest->sampleaspect = src->sampleaspect;
+ dest->framelength = src->framelength;
+ y4m_copy_xtag_list (&(dest->x_tags), &(src->x_tags));
+}
+
+
+void
+y4m_fini_stream_info (y4m_stream_info_t * info)
+{
+ if (info == NULL)
+ return;
+ y4m_fini_xtag_list (&(info->x_tags));
+}
+
+
+void
+y4m_si_set_width (y4m_stream_info_t * si, int width)
+{
+ si->width = width;
+ si->framelength = (si->height * si->width) * 3 / 2;
+}
+
+int
+y4m_si_get_width (const y4m_stream_info_t * si)
+{
+ return si->width;
+}
+
+void
+y4m_si_set_height (y4m_stream_info_t * si, int height)
+{
+ si->height = height;
+ si->framelength = (si->height * si->width) * 3 / 2;
+}
+
+int
+y4m_si_get_height (const y4m_stream_info_t * si)
+{
+ return si->height;
+}
+
+void
+y4m_si_set_interlace (y4m_stream_info_t * si, int interlace)
+{
+ si->interlace = interlace;
+}
+
+int
+y4m_si_get_interlace (const y4m_stream_info_t * si)
+{
+ return si->interlace;
+}
+
+void
+y4m_si_set_framerate (y4m_stream_info_t * si, y4m_ratio_t framerate)
+{
+ si->framerate = framerate;
+}
+
+y4m_ratio_t
+y4m_si_get_framerate (const y4m_stream_info_t * si)
+{
+ return si->framerate;
+}
+
+void
+y4m_si_set_sampleaspect (y4m_stream_info_t * si, y4m_ratio_t sar)
+{
+ si->sampleaspect = sar;
+}
+
+y4m_ratio_t
+y4m_si_get_sampleaspect (const y4m_stream_info_t * si)
+{
+ return si->sampleaspect;
+}
+
+int
+y4m_si_get_framelength (const y4m_stream_info_t * si)
+{
+ return si->framelength;
+}
+
+y4m_xtag_list_t *
+y4m_si_xtags (y4m_stream_info_t * si)
+{
+ return &(si->x_tags);
+}
+
+
+
+void
+y4m_init_frame_info (y4m_frame_info_t * info)
+{
+ if (info == NULL)
+ return;
+ /* initialize info */
+ y4m_init_xtag_list (&(info->x_tags));
+}
+
+
+void
+y4m_copy_frame_info (y4m_frame_info_t * dest, const y4m_frame_info_t * src)
+{
+ if ((dest == NULL) || (src == NULL))
+ return;
+ /* copy info */
+ y4m_copy_xtag_list (&(dest->x_tags), &(src->x_tags));
+}
+
+
+void
+y4m_fini_frame_info (y4m_frame_info_t * info)
+{
+ if (info == NULL)
+ return;
+ y4m_fini_xtag_list (&(info->x_tags));
+}
+
+
+
+/*************************************************************************
+ *
+ * Tag parsing
+ *
+ *************************************************************************/
+
+int
+y4m_parse_stream_tags (char *s, y4m_stream_info_t * i)
+{
+ char *token, *value;
+ char tag;
+ int err;
+
+ /* parse fields */
+ for (token = strtok (s, Y4M_DELIM); token != NULL; token = strtok (NULL, Y4M_DELIM)) {
+ if (token[0] == '\0')
+ continue; /* skip empty strings */
+ tag = token[0];
+ value = token + 1;
+ switch (tag) {
+ case 'W': /* width */
+ i->width = atoi (value);
+ if (i->width <= 0)
+ return Y4M_ERR_RANGE;
+ break;
+ case 'H': /* height */
+ i->height = atoi (value);
+ if (i->height <= 0)
+ return Y4M_ERR_RANGE;
+ break;
+ case 'F': /* frame rate (fps) */
+ if ((err = y4m_parse_ratio (&(i->framerate), value)) != Y4M_OK)
+ return err;
+ if (i->framerate.n < 0)
+ return Y4M_ERR_RANGE;
+ break;
+ case 'I': /* interlacing */
+ switch (value[0]) {
+ case 'p':
+ i->interlace = Y4M_ILACE_NONE;
+ break;
+ case 't':
+ i->interlace = Y4M_ILACE_TOP_FIRST;
+ break;
+ case 'b':
+ i->interlace = Y4M_ILACE_BOTTOM_FIRST;
+ break;
+ case '?':
+ default:
+ i->interlace = Y4M_UNKNOWN;
+ break;
+ }
+ break;
+ case 'A': /* sample (pixel) aspect ratio */
+ if ((err = y4m_parse_ratio (&(i->sampleaspect), value)) != Y4M_OK)
+ return err;
+ if (i->sampleaspect.n < 0)
+ return Y4M_ERR_RANGE;
+ break;
+ case 'X': /* 'X' meta-tag */
+ if ((err = y4m_xtag_add (&(i->x_tags), token)) != Y4M_OK)
+ return err;
+ break;
+ default:
+ /* possible error on unknown options */
+ if (_y4mparam_allow_unknown_tags) {
+ /* unknown tags ok: store in xtag list and warn... */
+ if ((err = y4m_xtag_add (&(i->x_tags), token)) != Y4M_OK)
+ return err;
+ mjpeg_warn ("Unknown stream tag encountered: '%s'", token);
+ } else {
+ /* unknown tags are *not* ok */
+ return Y4M_ERR_BADTAG;
+ }
+ break;
+ }
+ }
+ /* Error checking... width and height must be known since we can't
+ * parse without them
+ */
+ if (i->width == Y4M_UNKNOWN || i->height == Y4M_UNKNOWN)
+ return Y4M_ERR_HEADER;
+ /* ta da! done. */
+ return Y4M_OK;
+}
+
+
+
+static int
+y4m_parse_frame_tags (char *s, y4m_frame_info_t * i)
+{
+ char *token, *value;
+ char tag;
+ int err;
+
+ /* parse fields */
+ for (token = strtok (s, Y4M_DELIM); token != NULL; token = strtok (NULL, Y4M_DELIM)) {
+ if (token[0] == '\0')
+ continue; /* skip empty strings */
+ tag = token[0];
+ value = token + 1;
+ switch (tag) {
+ case 'X': /* 'X' meta-tag */
+ if ((err = y4m_xtag_add (&(i->x_tags), token)) != Y4M_OK)
+ return err;
+ break;
+ default:
+ /* possible error on unknown options */
+ if (_y4mparam_allow_unknown_tags) {
+ /* unknown tags ok: store in xtag list and warn... */
+ if ((err = y4m_xtag_add (&(i->x_tags), token)) != Y4M_OK)
+ return err;
+ mjpeg_warn ("Unknown frame tag encountered: '%s'", token);
+ } else {
+ /* unknown tags are *not* ok */
+ return Y4M_ERR_BADTAG;
+ }
+ break;
+ }
+ }
+ /* ta da! done. */
+ return Y4M_OK;
+}
+
+
+
+
+
+/*************************************************************************
+ *
+ * Read/Write stream header
+ *
+ *************************************************************************/
+
+
+int
+y4m_read_stream_header (int fd, y4m_stream_info_t * i)
+{
+ char line[Y4M_LINE_MAX];
+ char *p;
+ int n;
+ int err;
+
+ /* read the header line */
+ for (n = 0, p = line; n < Y4M_LINE_MAX; n++, p++) {
+ if (read (fd, p, 1) < 1)
+ return Y4M_ERR_SYSTEM;
+ if (*p == '\n') {
+ *p = '\0'; /* Replace linefeed by end of string */
+ break;
+ }
+ }
+ if (n >= Y4M_LINE_MAX)
+ return Y4M_ERR_HEADER;
+ /* look for keyword in header */
+ if (strncmp (line, Y4M_MAGIC, strlen (Y4M_MAGIC)))
+ return Y4M_ERR_MAGIC;
+ if ((err = y4m_parse_stream_tags (line + strlen (Y4M_MAGIC), i)) != Y4M_OK)
+ return err;
+
+ i->framelength = (i->height * i->width) * 3 / 2;
+ return Y4M_OK;
+}
+
+
+
+int
+y4m_write_stream_header (int fd, const y4m_stream_info_t * i)
+{
+ char s[Y4M_LINE_MAX + 1];
+ int n;
+ int err;
+ y4m_ratio_t rate = i->framerate;
+ y4m_ratio_t aspect = i->sampleaspect;
+
+ y4m_ratio_reduce (&rate);
+ y4m_ratio_reduce (&aspect);
+ n = snprintf (s, sizeof (s), "%s W%d H%d F%d:%d I%s A%d:%d",
+ Y4M_MAGIC,
+ i->width,
+ i->height,
+ rate.n, rate.d,
+ (i->interlace == Y4M_ILACE_NONE) ? "p" :
+ (i->interlace == Y4M_ILACE_TOP_FIRST) ? "t" :
+ (i->interlace == Y4M_ILACE_BOTTOM_FIRST) ? "b" : "?", aspect.n, aspect.d);
+ if ((n < 0) || (n > Y4M_LINE_MAX))
+ return Y4M_ERR_HEADER;
+ if ((err = y4m_snprint_xtags (s + n, sizeof (s) - n - 1, &(i->x_tags)))
+ != Y4M_OK)
+ return err;
+ /* non-zero on error */
+ return (y4m_write (fd, s, strlen (s)) ? Y4M_ERR_SYSTEM : Y4M_OK);
+}
+
+
+
+
+
+/*************************************************************************
+ *
+ * Read/Write frame header
+ *
+ *************************************************************************/
+
+int
+y4m_read_frame_header (int fd, y4m_frame_info_t * i)
+{
+ char line[Y4M_LINE_MAX];
+ char *p;
+ int n;
+ ssize_t remain;
+
+ /* This is more clever than read_stream_header...
+ Try to read "FRAME\n" all at once, and don't try to parse
+ if nothing else is there...
+ */
+ remain = y4m_read (fd, line, sizeof (Y4M_FRAME_MAGIC) - 1 + 1); /* -'\0', +'\n' */
+ if (remain < 0)
+ return Y4M_ERR_SYSTEM;
+ if (remain > 0) {
+ /* A clean EOF should end exactly at a frame-boundary */
+ if (remain == sizeof (Y4M_FRAME_MAGIC))
+ return Y4M_ERR_EOF;
+ else
+ return Y4M_ERR_BADEOF;
+ }
+ if (strncmp (line, Y4M_FRAME_MAGIC, sizeof (Y4M_FRAME_MAGIC) - 1))
+ return Y4M_ERR_MAGIC;
+ if (line[sizeof (Y4M_FRAME_MAGIC) - 1] == '\n')
+ return Y4M_OK; /* done -- no tags: that was the end-of-line. */
+
+ if (line[sizeof (Y4M_FRAME_MAGIC) - 1] != Y4M_DELIM[0]) {
+ return Y4M_ERR_MAGIC; /* wasn't a space -- what was it? */
+ }
+
+ /* proceed to get the tags... (overwrite the magic) */
+ for (n = 0, p = line; n < Y4M_LINE_MAX; n++, p++) {
+ if (y4m_read (fd, p, 1))
+ return Y4M_ERR_SYSTEM;
+ if (*p == '\n') {
+ *p = '\0'; /* Replace linefeed by end of string */
+ break;
+ }
+ }
+ if (n >= Y4M_LINE_MAX)
+ return Y4M_ERR_HEADER;
+ /* non-zero on error */
+ return y4m_parse_frame_tags (line, i);
+}
+
+
+int
+y4m_write_frame_header (int fd, const y4m_frame_info_t * i)
+{
+ char s[Y4M_LINE_MAX + 1];
+ int n;
+ int err;
+
+ 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, &(i->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 (int fd, const y4m_stream_info_t * si, y4m_frame_info_t * fi, uint8_t * const yuv[3])
+{
+ int err;
+ int w = si->width;
+ int h = si->height;
+
+ /* Read frame header */
+ if ((err = y4m_read_frame_header (fd, 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 / 4))
+ return Y4M_ERR_SYSTEM;
+ if (y4m_read (fd, yuv[2], w * h / 4))
+ return Y4M_ERR_SYSTEM;
+
+ return Y4M_OK;
+}
+
+
+
+
+int
+y4m_write_frame (int fd, const y4m_stream_info_t * si,
+ const y4m_frame_info_t * fi, uint8_t * const yuv[3])
+{
+ int err;
+ int w = si->width;
+ int h = si->height;
+
+ /* Write frame header */
+ if ((err = y4m_write_frame_header (fd, fi)) != Y4M_OK)
+ return err;
+ /* Write luminance,chrominance scanlines */
+ if (y4m_write (fd, yuv[0], w * h) ||
+ y4m_write (fd, yuv[1], w * h / 4) || y4m_write (fd, yuv[2], w * h / 4))
+ return Y4M_ERR_SYSTEM;
+ return Y4M_OK;
+}
+
+
+
+/*************************************************************************
+ *
+ * Read/Write entire frame, (de)interleaved (to)from two separate fields
+ *
+ *************************************************************************/
+
+
+int
+y4m_read_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 = 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++) {
+ 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;
+ }
+ /* for chroma, width/height are half as big */
+ if (i == 0) {
+ width /= 2;
+ height /= 2;
+ }
+ }
+ return Y4M_OK;
+}
+
+
+
+int
+y4m_write_fields (int fd, const y4m_stream_info_t * si,
+ const y4m_frame_info_t * fi,
+ uint8_t * const upper_field[3], uint8_t * const lower_field[3])
+{
+ int i, y, err;
+ int width = si->width;
+ int height = si->height;
+
+ /* Write frame header */
+ if ((err = y4m_write_frame_header (fd, fi)) != Y4M_OK)
+ return err;
+ /* Write 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_write (fd, srctop, width))
+ return Y4M_ERR_SYSTEM;
+ srctop += width;
+ if (y4m_write (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;
+}
+
+
+
+/*************************************************************************
+ *
+ * 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);
+ if (i->framelength == Y4M_UNKNOWN)
+ snprintf (s + strlen (s), sizeof (s) - strlen (s), "(? bytes)");
+ else
+ snprintf (s + strlen (s), sizeof (s) - strlen (s), "(%d bytes)", i->framelength);
+ mjpeg_log (level, "%s%s", prefix, s);
+ 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" : "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)";
+ default:
+ return "unknown error code";
+ }
+}