gstreamer/gst-libs/gst/video/convertframe.c
2011-08-25 16:30:49 +02:00

697 lines
19 KiB
C

/* Small helper element for format conversion
* Copyright (C) 2005 Tim-Philipp Müller <tim centricular net>
* Copyright (C) 2010 Brandon Lewis <brandon.lewis@collabora.co.uk>
* Copyright (C) 2010 Edward Hervey <edward.hervey@collabora.co.uk>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <string.h>
#include "video.h"
static gboolean
caps_are_raw (const GstCaps * caps)
{
guint i, len;
len = gst_caps_get_size (caps);
for (i = 0; i < len; i++) {
GstStructure *st = gst_caps_get_structure (caps, i);
if (gst_structure_has_name (st, "video/x-raw"))
return TRUE;
}
return FALSE;
}
static gboolean
create_element (const gchar * factory_name, GstElement ** element,
GError ** err)
{
*element = gst_element_factory_make (factory_name, NULL);
if (*element)
return TRUE;
if (err && *err == NULL) {
*err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_MISSING_PLUGIN,
"cannot create element '%s' - please check your GStreamer installation",
factory_name);
}
return FALSE;
}
static GstElement *
get_encoder (const GstCaps * caps, GError ** err)
{
GList *encoders = NULL;
GList *filtered = NULL;
GstElementFactory *factory = NULL;
GstElement *encoder = NULL;
encoders =
gst_element_factory_list_get_elements (GST_ELEMENT_FACTORY_TYPE_ENCODER |
GST_ELEMENT_FACTORY_TYPE_MEDIA_IMAGE, GST_RANK_NONE);
if (encoders == NULL) {
*err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_MISSING_PLUGIN,
"Cannot find any image encoder");
goto fail;
}
GST_INFO ("got factory list %p", encoders);
gst_plugin_feature_list_debug (encoders);
filtered =
gst_element_factory_list_filter (encoders, caps, GST_PAD_SRC, FALSE);
GST_INFO ("got filtered list %p", filtered);
if (filtered == NULL) {
gchar *tmp = gst_caps_to_string (caps);
*err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_MISSING_PLUGIN,
"Cannot find any image encoder for caps %s", tmp);
g_free (tmp);
goto fail;
}
gst_plugin_feature_list_debug (filtered);
factory = (GstElementFactory *) filtered->data;
GST_INFO ("got factory %p", factory);
encoder = gst_element_factory_create (factory, NULL);
GST_INFO ("created encoder element %p, %s", encoder,
gst_element_get_name (encoder));
fail:
if (encoders)
gst_plugin_feature_list_free (encoders);
if (filtered)
gst_plugin_feature_list_free (filtered);
return encoder;
}
static GstElement *
build_convert_frame_pipeline (GstElement ** src_element,
GstElement ** sink_element, const GstCaps * from_caps,
const GstCaps * to_caps, GError ** err)
{
GstElement *src = NULL, *csp = NULL, *vscale = NULL;
GstElement *sink = NULL, *encoder = NULL, *pipeline;
GError *error = NULL;
/* videoscale is here to correct for the pixel-aspect-ratio for us */
GST_DEBUG ("creating elements");
if (!create_element ("appsrc", &src, &error) ||
!create_element ("videoconvert", &csp, &error) ||
!create_element ("videoscale", &vscale, &error) ||
!create_element ("appsink", &sink, &error))
goto no_elements;
pipeline = gst_pipeline_new ("videoconvert-pipeline");
if (pipeline == NULL)
goto no_pipeline;
/* Add black borders if necessary to keep the DAR */
g_object_set (vscale, "add-borders", TRUE, NULL);
GST_DEBUG ("adding elements");
gst_bin_add_many (GST_BIN (pipeline), src, csp, vscale, sink, NULL);
/* set caps */
g_object_set (src, "caps", from_caps, NULL);
g_object_set (sink, "caps", to_caps, NULL);
/* FIXME: linking is still way too expensive, profile this properly */
GST_DEBUG ("linking src->csp");
if (!gst_element_link_pads (src, "src", csp, "sink"))
goto link_failed;
GST_DEBUG ("linking csp->vscale");
if (!gst_element_link_pads (csp, "src", vscale, "sink"))
goto link_failed;
if (caps_are_raw (to_caps)) {
GST_DEBUG ("linking vscale->sink");
if (!gst_element_link_pads (vscale, "src", sink, "sink"))
goto link_failed;
} else {
encoder = get_encoder (to_caps, &error);
if (!encoder)
goto no_encoder;
gst_bin_add (GST_BIN (pipeline), encoder);
GST_DEBUG ("linking vscale->encoder");
if (!gst_element_link (vscale, encoder))
goto link_failed;
GST_DEBUG ("linking encoder->sink");
if (!gst_element_link_pads (encoder, "src", sink, "sink"))
goto link_failed;
}
g_object_set (src, "emit-signals", TRUE, NULL);
g_object_set (sink, "emit-signals", TRUE, NULL);
*src_element = src;
*sink_element = sink;
return pipeline;
/* ERRORS */
no_encoder:
{
gst_object_unref (pipeline);
GST_ERROR ("could not find an encoder for provided caps");
if (err)
*err = error;
else
g_error_free (error);
return NULL;
}
no_elements:
{
if (src)
gst_object_unref (src);
if (csp)
gst_object_unref (csp);
if (vscale)
gst_object_unref (vscale);
if (sink)
gst_object_unref (sink);
GST_ERROR ("Could not convert video frame: %s", error->message);
if (err)
*err = error;
else
g_error_free (error);
return NULL;
}
no_pipeline:
{
gst_object_unref (src);
gst_object_unref (csp);
gst_object_unref (vscale);
gst_object_unref (sink);
GST_ERROR ("Could not convert video frame: no pipeline (unknown error)");
if (err)
*err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_FAILED,
"Could not convert video frame: no pipeline (unknown error)");
return NULL;
}
link_failed:
{
gst_object_unref (pipeline);
GST_ERROR ("Could not convert video frame: failed to link elements");
if (err)
*err = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_NEGOTIATION,
"Could not convert video frame: failed to link elements");
return NULL;
}
}
/**
* gst_video_convert_frame:
* @buf: a #GstBuffer
* @from_caps: the #GstCaps to convert from
* @to_caps: the #GstCaps to convert to
* @timeout: the maximum amount of time allowed for the processing.
* @error: pointer to a #GError. Can be %NULL.
*
* Converts a raw video buffer into the specified output caps.
*
* The output caps can be any raw video formats or any image formats (jpeg, png, ...).
*
* The width, height and pixel-aspect-ratio can also be specified in the output caps.
*
* Returns: The converted #GstBuffer, or %NULL if an error happened (in which case @err
* will point to the #GError).
*
* Since: 0.10.31
*
*/
GstBuffer *
gst_video_convert_frame (GstBuffer * buf, GstCaps * from_caps,
const GstCaps * to_caps, GstClockTime timeout, GError ** error)
{
GstMessage *msg;
GstBuffer *result = NULL;
GError *err = NULL;
GstBus *bus;
GstCaps *to_caps_copy = NULL;
GstFlowReturn ret;
GstElement *pipeline, *src, *sink;
guint i, n;
g_return_val_if_fail (buf != NULL, NULL);
g_return_val_if_fail (to_caps != NULL, NULL);
g_return_val_if_fail (from_caps != NULL, NULL);
to_caps_copy = gst_caps_new_empty ();
n = gst_caps_get_size (to_caps);
for (i = 0; i < n; i++) {
GstStructure *s = gst_caps_get_structure (to_caps, i);
s = gst_structure_copy (s);
gst_structure_remove_field (s, "framerate");
gst_caps_append_structure (to_caps_copy, s);
}
pipeline =
build_convert_frame_pipeline (&src, &sink, from_caps, to_caps_copy, &err);
if (!pipeline)
goto no_pipeline;
/* now set the pipeline to the paused state, after we push the buffer into
* appsrc, this should preroll the converted buffer in appsink */
GST_DEBUG ("running conversion pipeline to caps %" GST_PTR_FORMAT,
to_caps_copy);
gst_element_set_state (pipeline, GST_STATE_PAUSED);
/* feed buffer in appsrc */
GST_DEBUG ("feeding buffer %p, size %" G_GSIZE_FORMAT ", caps %"
GST_PTR_FORMAT, buf, gst_buffer_get_size (buf), from_caps);
g_signal_emit_by_name (src, "push-buffer", buf, &ret);
/* now see what happens. We either got an error somewhere or the pipeline
* prerolled */
bus = gst_element_get_bus (pipeline);
msg = gst_bus_timed_pop_filtered (bus,
timeout, GST_MESSAGE_ERROR | GST_MESSAGE_ASYNC_DONE);
if (msg) {
switch (GST_MESSAGE_TYPE (msg)) {
case GST_MESSAGE_ASYNC_DONE:
{
/* we're prerolled, get the frame from appsink */
g_signal_emit_by_name (sink, "pull-preroll", &result);
if (result) {
GST_DEBUG ("conversion successful: result = %p", result);
} else {
GST_ERROR ("prerolled but no result frame?!");
}
break;
}
case GST_MESSAGE_ERROR:{
gchar *dbg = NULL;
gst_message_parse_error (msg, &err, &dbg);
if (err) {
GST_ERROR ("Could not convert video frame: %s", err->message);
GST_DEBUG ("%s [debug: %s]", err->message, GST_STR_NULL (dbg));
if (error)
*error = err;
else
g_error_free (err);
}
g_free (dbg);
break;
}
default:{
g_return_val_if_reached (NULL);
}
}
gst_message_unref (msg);
} else {
GST_ERROR ("Could not convert video frame: timeout during conversion");
if (error)
*error = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_FAILED,
"Could not convert video frame: timeout during conversion");
}
gst_element_set_state (pipeline, GST_STATE_NULL);
gst_object_unref (bus);
gst_object_unref (pipeline);
gst_caps_unref (to_caps_copy);
return result;
/* ERRORS */
no_pipeline:
{
gst_caps_unref (to_caps_copy);
if (error)
*error = err;
else
g_error_free (err);
return NULL;
}
}
typedef struct
{
GMutex *mutex;
GstElement *pipeline;
GstVideoConvertFrameCallback callback;
gpointer user_data;
GDestroyNotify destroy_notify;
GMainContext *context;
GstBuffer *buffer;
gulong timeout_id;
gboolean finished;
} GstVideoConvertFrameContext;
typedef struct
{
GstVideoConvertFrameCallback callback;
GstBuffer *buffer;
GError *error;
gpointer user_data;
GDestroyNotify destroy_notify;
GstVideoConvertFrameContext *context;
} GstVideoConvertFrameCallbackContext;
static void
gst_video_convert_frame_context_free (GstVideoConvertFrameContext * ctx)
{
/* Wait until all users of the mutex are done */
g_mutex_lock (ctx->mutex);
g_mutex_unlock (ctx->mutex);
g_mutex_free (ctx->mutex);
if (ctx->timeout_id)
g_source_remove (ctx->timeout_id);
if (ctx->buffer)
gst_buffer_unref (ctx->buffer);
g_main_context_unref (ctx->context);
gst_element_set_state (ctx->pipeline, GST_STATE_NULL);
gst_object_unref (ctx->pipeline);
g_slice_free (GstVideoConvertFrameContext, ctx);
}
static void
gst_video_convert_frame_callback_context_free
(GstVideoConvertFrameCallbackContext * ctx)
{
if (ctx->context)
gst_video_convert_frame_context_free (ctx->context);
g_slice_free (GstVideoConvertFrameCallbackContext, ctx);
}
static gboolean
convert_frame_dispatch_callback (GstVideoConvertFrameCallbackContext * ctx)
{
ctx->callback (ctx->buffer, ctx->error, ctx->user_data);
if (ctx->destroy_notify)
ctx->destroy_notify (ctx->user_data);
return FALSE;
}
static void
convert_frame_finish (GstVideoConvertFrameContext * context, GstBuffer * buffer,
GError * error)
{
GSource *source;
GstVideoConvertFrameCallbackContext *ctx;
if (context->timeout_id)
g_source_remove (context->timeout_id);
context->timeout_id = 0;
ctx = g_slice_new (GstVideoConvertFrameCallbackContext);
ctx->callback = context->callback;
ctx->user_data = context->user_data;
ctx->destroy_notify = context->destroy_notify;
ctx->buffer = buffer;
ctx->error = error;
ctx->context = context;
source = g_timeout_source_new (0);
g_source_set_callback (source,
(GSourceFunc) convert_frame_dispatch_callback, ctx,
(GDestroyNotify) gst_video_convert_frame_callback_context_free);
g_source_attach (source, context->context);
g_source_unref (source);
context->finished = TRUE;
}
static gboolean
convert_frame_timeout_callback (GstVideoConvertFrameContext * context)
{
GError *error;
g_mutex_lock (context->mutex);
if (context->finished)
goto done;
GST_ERROR ("Could not convert video frame: timeout");
error = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_FAILED,
"Could not convert video frame: timeout");
convert_frame_finish (context, NULL, error);
done:
g_mutex_unlock (context->mutex);
return FALSE;
}
static gboolean
convert_frame_bus_callback (GstBus * bus, GstMessage * message,
GstVideoConvertFrameContext * context)
{
g_mutex_lock (context->mutex);
if (context->finished)
goto done;
switch (GST_MESSAGE_TYPE (message)) {
case GST_MESSAGE_ERROR:{
GError *error;
gchar *dbg = NULL;
gst_message_parse_error (message, &error, &dbg);
GST_ERROR ("Could not convert video frame: %s", error->message);
GST_DEBUG ("%s [debug: %s]", error->message, GST_STR_NULL (dbg));
convert_frame_finish (context, NULL, error);
g_free (dbg);
break;
}
default:
break;
}
done:
g_mutex_unlock (context->mutex);
return FALSE;
}
static void
convert_frame_need_data_callback (GstElement * src, guint size,
GstVideoConvertFrameContext * context)
{
GstFlowReturn ret = GST_FLOW_ERROR;
GError *error;
g_mutex_lock (context->mutex);
if (context->finished)
goto done;
g_signal_emit_by_name (src, "push-buffer", context->buffer, &ret);
gst_buffer_unref (context->buffer);
context->buffer = NULL;
if (ret != GST_FLOW_OK) {
GST_ERROR ("Could not push video frame: %s", gst_flow_get_name (ret));
error = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_FAILED,
"Could not push video frame: %s", gst_flow_get_name (ret));
convert_frame_finish (context, NULL, error);
}
g_signal_handlers_disconnect_by_func (src, convert_frame_need_data_callback,
context);
done:
g_mutex_unlock (context->mutex);
}
static void
convert_frame_new_buffer_callback (GstElement * sink,
GstVideoConvertFrameContext * context)
{
GstBuffer *buf = NULL;
GError *error = NULL;
g_mutex_lock (context->mutex);
if (context->finished)
goto done;
g_signal_emit_by_name (sink, "pull-preroll", &buf);
if (!buf) {
error = g_error_new (GST_CORE_ERROR, GST_CORE_ERROR_FAILED,
"Could not get converted video frame");
}
convert_frame_finish (context, buf, error);
g_signal_handlers_disconnect_by_func (sink, convert_frame_need_data_callback,
context);
done:
g_mutex_unlock (context->mutex);
}
/**
* gst_video_convert_frame_async:
* @buf: a #GstBuffer
* @to_caps: the #GstCaps to convert to
* @timeout: the maximum amount of time allowed for the processing.
* @callback: %GstVideoConvertFrameCallback that will be called after conversion.
* @user_data: extra data that will be passed to the @callback
* @destroy_notify: %GDestroyNotify to be called after @user_data is not needed anymore
*
* Converts a raw video buffer into the specified output caps.
*
* The output caps can be any raw video formats or any image formats (jpeg, png, ...).
*
* The width, height and pixel-aspect-ratio can also be specified in the output caps.
*
* @callback will be called after conversion, when an error occured or if conversion didn't
* finish after @timeout. @callback will always be called from the thread default
* %GMainContext, see g_main_context_get_thread_default(). If GLib before 2.22 is used,
* this will always be the global default main context.
*
* @destroy_notify will be called after the callback was called and @user_data is not needed
* anymore.
*
* Since: 0.10.31
*
*/
void
gst_video_convert_frame_async (GstBuffer * buf, GstCaps * from_caps,
const GstCaps * to_caps, GstClockTime timeout,
GstVideoConvertFrameCallback callback, gpointer user_data,
GDestroyNotify destroy_notify)
{
GMainContext *context = NULL;
GError *error = NULL;
GstBus *bus;
GstCaps *to_caps_copy = NULL;
GstElement *pipeline, *src, *sink;
guint i, n;
GSource *source;
GstVideoConvertFrameContext *ctx;
g_return_if_fail (buf != NULL);
g_return_if_fail (to_caps != NULL);
g_return_if_fail (from_caps != NULL);
g_return_if_fail (callback != NULL);
context = g_main_context_get_thread_default ();
if (!context)
context = g_main_context_default ();
to_caps_copy = gst_caps_new_empty ();
n = gst_caps_get_size (to_caps);
for (i = 0; i < n; i++) {
GstStructure *s = gst_caps_get_structure (to_caps, i);
s = gst_structure_copy (s);
gst_structure_remove_field (s, "framerate");
gst_caps_append_structure (to_caps_copy, s);
}
pipeline =
build_convert_frame_pipeline (&src, &sink, from_caps, to_caps_copy,
&error);
if (!pipeline)
goto no_pipeline;
bus = gst_element_get_bus (pipeline);
ctx = g_slice_new0 (GstVideoConvertFrameContext);
ctx->mutex = g_mutex_new ();
ctx->buffer = gst_buffer_ref (buf);
ctx->callback = callback;
ctx->user_data = user_data;
ctx->destroy_notify = destroy_notify;
ctx->context = g_main_context_ref (context);
ctx->finished = FALSE;
ctx->pipeline = pipeline;
if (timeout != GST_CLOCK_TIME_NONE) {
source = g_timeout_source_new (timeout / GST_MSECOND);
g_source_set_callback (source,
(GSourceFunc) convert_frame_timeout_callback, ctx, NULL);
ctx->timeout_id = g_source_attach (source, context);
g_source_unref (source);
}
g_signal_connect (src, "need-data",
G_CALLBACK (convert_frame_need_data_callback), ctx);
g_signal_connect (sink, "new-preroll",
G_CALLBACK (convert_frame_new_buffer_callback), ctx);
source = gst_bus_create_watch (bus);
g_source_set_callback (source, (GSourceFunc) convert_frame_bus_callback,
ctx, NULL);
g_source_attach (source, context);
g_source_unref (source);
gst_element_set_state (pipeline, GST_STATE_PLAYING);
gst_object_unref (bus);
gst_caps_unref (to_caps_copy);
return;
/* ERRORS */
no_pipeline:
{
GstVideoConvertFrameCallbackContext *ctx;
GSource *source;
gst_caps_unref (to_caps_copy);
ctx = g_slice_new0 (GstVideoConvertFrameCallbackContext);
ctx->callback = callback;
ctx->user_data = user_data;
ctx->destroy_notify = destroy_notify;
ctx->buffer = NULL;
ctx->error = error;
source = g_timeout_source_new (0);
g_source_set_callback (source,
(GSourceFunc) convert_frame_dispatch_callback, ctx,
(GDestroyNotify) gst_video_convert_frame_callback_context_free);
g_source_attach (source, context);
g_source_unref (source);
}
}