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mpeg4videoparse: parse more forms of codec_data

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This commit is contained in:
Michael Smith 2010-01-16 13:17:08 -08:00
parent 88009080e8
commit c2b1bebc02
1 changed files with 51 additions and 9 deletions
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62
gst/mpeg4videoparse/mpeg4videoparse.c
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@ -120,6 +120,8 @@ gst_mpeg4vparse_set_new_caps (GstMpeg4VParse * parse,
return res;
}
#define VIDEO_OBJECT_STARTCODE_MIN 0x00
#define VIDEO_OBJECT_STARTCODE_MAX 0x1F
#define VOS_STARTCODE 0xB0
#define VOS_ENDCODE 0xB1
#define USER_DATA_STARTCODE 0xB2
@ -215,6 +217,7 @@ static gint aspect_ratio_table[6][2] = { {-1, -1}, {1, 1}, {12, 11},
{10, 11}, {16, 11}, {40, 33}
};
/* Handle parsing a video object */
static gboolean
gst_mpeg4vparse_handle_vo (GstMpeg4VParse * parse, const guint8 * data,
gsize size)
@ -291,7 +294,7 @@ gst_mpeg4vparse_handle_vo (GstMpeg4VParse * parse, const guint8 * data,
/* fixed time increment */
int n;
/* Lenght of the time increment is the minimal number of bits needed to
/* Length of the time increment is the minimal number of bits needed to
* represent time_increment_resolution */
for (n = 0; (time_increment_resolution >> n) != 0; n++);
GET_BITS (&bs, n, &bits);
@ -347,7 +350,8 @@ failed:
return FALSE;
}
/* Returns whether we successfully set the caps downstream if needed */
/* Handle parsing a visual object sequence.
Returns whether we successfully set the caps downstream if needed */
static gboolean
gst_mpeg4vparse_handle_vos (GstMpeg4VParse * parse, const guint8 * data,
gsize size)
@ -368,11 +372,13 @@ gst_mpeg4vparse_handle_vos (GstMpeg4VParse * parse, const guint8 * data,
profile = data[4];
/* invalid profile, yikes */
if (profile == 0)
if (profile == 0) {
GST_WARNING_OBJECT (parse, "Invalid profile in VOS");
return FALSE;
}
equal = FALSE;
if (G_LIKELY (parse->config &&
if (G_LIKELY (parse->config && size == GST_BUFFER_SIZE (parse->config) &&
memcmp (GST_BUFFER_DATA (parse->config), data, size) == 0))
equal = TRUE;
@ -661,16 +667,52 @@ gst_mpeg4vparse_sink_setcaps (GstPad * pad, GstCaps * caps)
&& G_VALUE_HOLDS (value, GST_TYPE_BUFFER)) {
GstBuffer *buf = gst_value_get_buffer (value);
res = gst_mpeg4vparse_handle_vos (parse, GST_BUFFER_DATA (buf),
GST_BUFFER_SIZE (buf));
} else {
/* No codec data, set minimal new caps.. VOS parsing later will fill in
* the other fields */
res = gst_mpeg4vparse_set_new_caps (parse, 0, 0, 0, 0, 0, 0);
/* Set the config from this codec_data immediately so that in the worst
case, we don't just discard it.
Note that in most cases, this will be freed and overwritten when we
manage to parse the codec_data. */
if (!parse->config) {
parse->config = gst_buffer_copy (buf);
}
if (GST_BUFFER_SIZE (buf) < 4) {
GST_WARNING_OBJECT (parse, "codec_data too short, ignoring");
goto failed_parse;
} else {
const guint8 *data = GST_BUFFER_DATA (buf);
if (data[0] == 0 && data[1] == 0 && data[2] == 1) {
if (data[3] == VOS_STARTCODE) {
/* Usually the codec data will be a visual object sequence, containing
a visual object, with a video object/video object layer. */
res = gst_mpeg4vparse_handle_vos (parse, data, GST_BUFFER_SIZE (buf));
} else if (data[3] >= VIDEO_OBJECT_STARTCODE_MIN &&
data[3] <= VIDEO_OBJECT_STARTCODE_MAX) {
/* Sometimes, instead, it'll just have the video object/video object
layer data. We can parse that too, though it'll give us slightly
less information. */
res = gst_mpeg4vparse_handle_vo (parse, data, GST_BUFFER_SIZE (buf));
}
} else {
GST_WARNING_OBJECT (parse,
"codec_data does not begin with start code, invalid");
goto failed_parse;
}
}
} else {
/* No codec data; treat the same a failed codec data */
goto failed_parse;
}
done:
gst_object_unref (parse);
return res;
failed_parse:
/* No codec data, or obviously-invalid, so set minimal new caps.
VOS parsing later will (hopefully) fill in the other fields */
res = gst_mpeg4vparse_set_new_caps (parse, 0, 0, 0, 0, 0, 0);
goto done;
}
static gboolean