mirrors/gstreamer
mirrors/gstreamer
1
1
Fork 0
mirror of https://gitlab.freedesktop.org/gstreamer/gstreamer.git synced 2024-11-27 12:11:13 +00:00
Code Issues 1 Projects Releases Wiki Activity

basevideodecoder: add capture pattern handling

Browse source 
Move typical scan_for_sync() usage into base class, which just
calls gst_adapter_masked_scan_uint32().
This commit is contained in:
David Schleef 2010-09-18 19:21:47 -07:00
parent dbbf1182dc
commit 62a9383527
3 changed files with 41 additions and 52 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

36
ext/schroedinger/gstschrodec.c
View file

@ -90,8 +90,6 @@ static gboolean gst_schro_dec_stop (GstBaseVideoDecoder * dec);
static gboolean gst_schro_dec_reset (GstBaseVideoDecoder * dec);
static GstFlowReturn gst_schro_dec_parse_data (GstBaseVideoDecoder *
base_video_decoder, gboolean at_eos);
static int gst_schro_dec_scan_for_sync (GstBaseVideoDecoder *
base_video_decoder, gboolean at_eos, int offset, int n);
static GstFlowReturn gst_schro_dec_handle_frame (GstBaseVideoDecoder * decoder,
GstVideoFrame * frame);
static gboolean gst_schro_dec_finish (GstBaseVideoDecoder * base_video_decoder);
@ -150,11 +148,12 @@ gst_schro_dec_class_init (GstSchroDecClass * klass)
base_video_decoder_class->reset = GST_DEBUG_FUNCPTR (gst_schro_dec_reset);
base_video_decoder_class->parse_data =
GST_DEBUG_FUNCPTR (gst_schro_dec_parse_data);
base_video_decoder_class->scan_for_sync =
GST_DEBUG_FUNCPTR (gst_schro_dec_scan_for_sync);
base_video_decoder_class->handle_frame =
GST_DEBUG_FUNCPTR (gst_schro_dec_handle_frame);
base_video_decoder_class->finish = GST_DEBUG_FUNCPTR (gst_schro_dec_finish);
gst_base_video_decoder_class_set_capture_pattern (base_video_decoder_class,
0xffffffff, 0x42424344);
}
static void
@ -536,35 +535,6 @@ gst_schro_dec_parse_data (GstBaseVideoDecoder * base_video_decoder,
return GST_FLOW_OK;
}
static int
gst_schro_dec_scan_for_sync (GstBaseVideoDecoder * base_video_decoder,
gboolean at_eos, int offset, int n)
{
GstAdapter *adapter = base_video_decoder->input_adapter;
int n_available;
int ret;
n_available = gst_adapter_available (adapter) - offset;
if (n_available < 4) {
if (at_eos) {
return n_available;
} else {
return 0;
}
}
n = MIN (n, n_available - 3);
ret = gst_adapter_masked_scan_uint32 (adapter, 0xffffffff, 0x42424344,
offset, n);
if (ret == -1) {
return n;
}
return ret;
}
static void
gst_schrodec_send_tags (GstSchroDec * schro_dec)
{

52
gst-libs/gst/video/gstbasevideodecoder.c
View file

@ -862,32 +862,36 @@ gst_base_video_decoder_chain (GstPad * pad, GstBuffer * buf)
GST_DEBUG ("no sync, scanning");
n = gst_adapter_available (base_video_decoder->input_adapter);
m = klass->scan_for_sync (base_video_decoder, FALSE, 0, n);
if (klass->capture_mask != 0) {
m = gst_adapter_masked_scan_uint32 (base_video_decoder->input_adapter,
klass->capture_mask, klass->capture_pattern, 0, n - 3);
} else if (klass->scan_for_sync) {
m = klass->scan_for_sync (base_video_decoder, FALSE, 0, n);
} else {
m = 0;
}
if (m == -1) {
GST_ERROR ("scan returned no sync");
gst_adapter_flush (base_video_decoder->input_adapter, n - 3);
gst_object_unref (base_video_decoder);
return GST_FLOW_OK;
}
} else {
if (m > 0) {
if (m >= n) {
GST_ERROR ("subclass scanned past end %d >= %d", m, n);
}
if (m < 0) {
g_warning ("subclass returned negative scan %d", m);
}
gst_adapter_flush (base_video_decoder->input_adapter, m);
if (m >= n) {
GST_ERROR ("subclass scanned past end %d >= %d", m, n);
}
if (m < n) {
GST_DEBUG ("found possible sync after %d bytes (of %d)", m, n);
gst_adapter_flush (base_video_decoder->input_adapter, m);
/* this is only "maybe" sync */
base_video_decoder->have_sync = TRUE;
}
}
if (m < n) {
GST_DEBUG ("found possible sync after %d bytes (of %d)", m, n);
/* this is only "maybe" sync */
base_video_decoder->have_sync = TRUE;
}
if (!base_video_decoder->have_sync) {
gst_object_unref (base_video_decoder);
return GST_FLOW_OK;
}
}
@ -1496,3 +1500,13 @@ gst_base_video_decoder_get_max_decode_time (GstBaseVideoDecoder *
return deadline;
}
void
gst_base_video_decoder_class_set_capture_pattern (GstBaseVideoDecoderClass *
base_video_decoder_class, guint32 mask, guint32 pattern)
{
g_return_if_fail (((~mask) & pattern) == 0);
base_video_decoder_class->capture_mask = mask;
base_video_decoder_class->capture_pattern = pattern;
}

5
gst-libs/gst/video/gstbasevideodecoder.h
View file

@ -137,10 +137,15 @@ struct _GstBaseVideoDecoderClass
GstFlowReturn (*shape_output) (GstBaseVideoDecoder *coder, GstVideoFrame *frame);
GstCaps *(*get_caps) (GstBaseVideoDecoder *coder);
guint32 capture_mask;
guint32 capture_pattern;
};
GType gst_base_video_decoder_get_type (void);
void gst_base_video_decoder_class_set_capture_pattern (GstBaseVideoDecoderClass *klass,
guint32 mask, guint32 pattern);
int gst_base_video_decoder_get_width (GstBaseVideoDecoder *coder);
int gst_base_video_decoder_get_height (GstBaseVideoDecoder *coder);