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jpegparse: improve parsing

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Handle more app maker. Print app marker names to debug log. Remember last_marker
when parsing to avoid reparsing from the very begin.
This commit is contained in:
Stefan Kost 2010-02-02 11:22:06 +02:00
parent 6f1ee59df6
commit b9f8f5d281
2 changed files with 90 additions and 24 deletions
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3
gst/jpegformat/gstjpegformat.h
View file

@ -76,6 +76,9 @@ G_BEGIN_DECLS
#define APP0 0xe0 /* Application marker */
#define APP1 0xe1
#define APP2 0xe2
#define APP13 0xed
#define APP14 0xee
#define APP15 0xef
#define JPG0 0xf0 /* Reserved ... */

111
gst/jpegformat/gstjpegparse.c
View file

@ -43,6 +43,7 @@
#include <config.h>
#endif
#include <string.h>
#include <gst/base/gstbytereader.h>
#include "gstjpegparse.h"
@ -74,6 +75,7 @@ struct _GstJpegParsePrivate
GstPad *srcpad;
GstAdapter *adapter;
guint last_offset;
/* negotiated state */
gint caps_width, caps_height;
@ -256,6 +258,7 @@ gst_jpeg_parse_skip_to_jpeg_header (GstJpegParse * parse)
available = gst_adapter_available (parse->priv->adapter);
if (available < 4)
return FALSE;
flush = gst_adapter_masked_scan_uint32 (parse->priv->adapter, 0xffffff00,
0xffd8ff00, 0, available);
if (flush == -1) {
@ -300,24 +303,30 @@ gst_jpeg_parse_match_next_marker (const guint8 * data, guint size)
if (tag >= RST0 && tag <= EOI)
marker_len = 2;
else if (G_UNLIKELY (size < 4))
return -1;
goto need_more_data;
else
marker_len = GST_READ_UINT16_BE (data + 2) + 2;
GST_LOG ("Have marker %x with length %u", data[1], marker_len);
/* we log this in gst_jpeg_parse_find_end_marker() already
GST_LOG ("Have marker %x with length %u", data[1], marker_len);
*/
/* Need marker_len for this marker, plus two for the next marker. */
if (G_UNLIKELY (marker_len + 2 >= size))
return -1;
goto need_more_data;
if (G_UNLIKELY (gst_jpeg_parse_parse_tag_has_entropy_segment (tag))) {
while (!(data[marker_len] == 0xff && data[marker_len + 1] != 0x00)) {
if (G_UNLIKELY (marker_len + 2 >= size))
return -1;
++marker_len;
if (G_UNLIKELY (marker_len > size))
goto need_more_data;
}
}
return marker_len;
need_more_data:
GST_LOG ("need more data");
return -1;
}
/*
@ -334,7 +343,7 @@ static guint
gst_jpeg_parse_find_end_marker (GstJpegParse * parse, const guint8 * data,
guint size)
{
guint offset = 0;
guint offset = parse->priv->last_offset;
while (1) {
guint marker_len;
@ -343,6 +352,7 @@ gst_jpeg_parse_find_end_marker (GstJpegParse * parse, const guint8 * data,
if (offset + 1 >= size)
return -1;
/* all jpeg marker start with 0xff */
if (data[offset] != 0xff)
return -2;
@ -355,7 +365,8 @@ gst_jpeg_parse_find_end_marker (GstJpegParse * parse, const guint8 * data,
/* Check for EOI */
if (G_UNLIKELY (tag == EOI)) {
GST_DEBUG_OBJECT (parse, "EOI at %u", offset);
return offset + 2;
parse->priv->last_offset = offset;
return offset;
}
/* Skip over this marker. */
marker_len = gst_jpeg_parse_match_next_marker (data + offset,
@ -365,6 +376,8 @@ gst_jpeg_parse_find_end_marker (GstJpegParse * parse, const guint8 * data,
} else {
GST_LOG_OBJECT (parse, "At offset %u: marker %02x, length %u", offset,
tag, marker_len);
/* remember last found marker, so that we don't rescan from begin */
parse->priv->last_offset = offset;
offset += marker_len;
}
}
@ -375,7 +388,7 @@ static guint
gst_jpeg_parse_get_image_length (GstJpegParse * parse)
{
const guint8 *data;
guint size, offset, start = 2;
guint size, offset;
size = gst_adapter_available (parse->priv->adapter);
if (size < 4) {
@ -386,35 +399,34 @@ gst_jpeg_parse_get_image_length (GstJpegParse * parse)
g_return_val_if_fail (data[0] == 0xff && data[1] == SOI, 0);
GST_DEBUG_OBJECT (parse, "Parsing jpeg image data (%u bytes)", size);
/* skip start marker */
offset = gst_jpeg_parse_find_end_marker (parse, data + 2, size - 2);
offset = gst_jpeg_parse_find_end_marker (parse, data, size);
if (offset == -1) {
GST_DEBUG_OBJECT (parse, "Insufficient data.");
/* FIXME: remember size, so that we don't rescan from begin */
GST_LOG_OBJECT (parse, "Insufficient data.");
return 0;
} else if (G_UNLIKELY (offset == -2)) {
guint start = parse->priv->last_offset;
GST_DEBUG_OBJECT (parse, "Lost sync, resyncing.");
/* FIXME does this make sense at all? This can only happen for broken
* images, and the most likely breakage is that it's truncated. In that
* case, however, we should be looking for a new start marker... */
while (offset == -2 || offset == -1) {
start++;
/* scan for 0xff */
while (start + 1 < size && data[start] != 0xff)
start++;
if (G_UNLIKELY (start + 1 >= size)) {
GST_DEBUG_OBJECT (parse, "Insufficient data while resyncing.");
return 0;
}
GST_LOG_OBJECT (parse, "Resyncing from offset %u.", start);
offset = gst_jpeg_parse_find_end_marker (parse, data + start, size -
start);
GST_LOG_OBJECT (parse, "Resyncing from offset %u (size %u).",
start, size);
parse->priv->last_offset = start;
offset = gst_jpeg_parse_find_end_marker (parse, data, size);
}
}
return start + offset;
return offset;
}
static gboolean
@ -547,7 +559,21 @@ gst_jpeg_parse_read_header (GstJpegParse * parse, GstBuffer * buffer)
case APP0:
case APP1:
case APP15:
case APP2:
case APP13:
case APP14:
case APP15:{
const gchar *id_str;
if (!gst_byte_reader_get_uint16_be (&reader, &size))
goto error;
if (!gst_byte_reader_get_string_utf8 (&reader, &id_str))
goto error;
if (!gst_byte_reader_skip (&reader, size - 3 - strlen (id_str)))
goto error;
GST_LOG_OBJECT (parse, "unhandled marker %x: '%s' skiping %u bytes",
marker, id_str, size - 2);
break;
}
case DHT:
case DQT:
/* Ignore these codes */
@ -571,10 +597,38 @@ gst_jpeg_parse_read_header (GstJpegParse * parse, GstBuffer * buffer)
return TRUE;
default:
GST_WARNING_OBJECT (parse, "unhandled marker %x, leaving", marker);
/* Not SOF or SOI. Must not be a JPEG file (or file pointer
* is placed wrong). In either case, it's an error. */
return FALSE;
if (marker == JPG || (marker >= JPG0 && marker <= JPG13)) {
/* we'd like to remove them from the buffer */
#if 1
guint pos = gst_byte_reader_get_pos (&reader);
guint8 *data = GST_BUFFER_DATA (buffer);
if (!gst_byte_reader_peek_uint16_be (&reader, &size))
goto error;
if (gst_byte_reader_get_remaining (&reader) < size)
goto error;
GST_LOG_OBJECT (parse, "unhandled marker %x removing %u bytes",
marker, size);
memmove (&data[pos], &data[pos + size],
GST_BUFFER_SIZE (buffer) - (pos + size));
GST_BUFFER_SIZE (buffer) -= size;
reader.size -= size;
#else
if (!gst_byte_reader_get_uint16_be (&reader, &size))
goto error;
if (!gst_byte_reader_skip (&reader, size - 2))
goto error;
GST_LOG_OBJECT (parse, "unhandled marker %x skiping %u bytes", marker,
size - 2);
#endif
} else {
GST_WARNING_OBJECT (parse, "unhandled marker %x, leaving", marker);
/* Not SOF or SOI. Must not be a JPEG file (or file pointer
* is placed wrong). In either case, it's an error. */
return FALSE;
}
}
if (!gst_byte_reader_peek_uint8 (&reader, &marker))
@ -584,7 +638,9 @@ gst_jpeg_parse_read_header (GstJpegParse * parse, GstBuffer * buffer)
return foundSOF;
error:
GST_WARNING_OBJECT (parse, "Error parsing image header");
GST_WARNING_OBJECT (parse,
"Error parsing image header (need more that %u bytes available)",
gst_byte_reader_get_remaining (&reader));
return FALSE;
}
@ -642,6 +698,9 @@ gst_jpeg_parse_push_buffer (GstJpegParse * parse, guint len)
GstFlowReturn ret = GST_FLOW_OK;
gboolean header_ok;
/* reset the offset (only when we flushed) */
parse->priv->last_offset = 2;
outbuf = gst_adapter_take_buffer (parse->priv->adapter, len);
if (outbuf == NULL) {
GST_ELEMENT_ERROR (parse, STREAM, DECODE,
@ -716,10 +775,12 @@ gst_jpeg_parse_chain (GstPad * pad, GstBuffer * buf)
parse->priv->duration = duration;
/* check if we already have a EOI */
len = gst_jpeg_parse_get_image_length (parse);
if (len == 0)
return GST_FLOW_OK;
/* now we have enough in the adapter to process a full jpeg image */
ret = gst_jpeg_parse_push_buffer (parse, len);
}
@ -786,6 +847,8 @@ gst_jpeg_parse_change_state (GstElement * element, GstStateChange transition)
parse->priv->new_segment = FALSE;
parse->priv->next_ts = GST_CLOCK_TIME_NONE;
parse->priv->last_offset = 2;
default:
break;
}