gstreamer/ext/libpng/gstpngenc.c
Stefan Kost 9cf73bdd8f Update and add documentation for plugins with deps (ext).
Link to properties. Correct titles for examples. Document a few trivial cases. Keep lists in section file and docs/plugins/Makefile.am alphabetically ordered. Fix warnings that gtk-doc points out.
2009-01-28 18:05:09 +02:00

396 lines
11 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* Filter:
* Copyright (C) 2000 Donald A. Graft
*
* 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.
*
*/
/**
* SECTION:element-pngenc
*
* Encodes png images.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include <gst/gst.h>
#include "gstpngenc.h"
#include <gst/video/video.h>
#include <zlib.h>
#define MAX_HEIGHT 4096
static const GstElementDetails gst_pngenc_details =
GST_ELEMENT_DETAILS ("PNG image encoder",
"Codec/Encoder/Image",
"Encode a video frame to a .png image",
"Jeremy SIMON <jsimon13@yahoo.fr>");
GST_DEBUG_CATEGORY_STATIC (pngenc_debug);
#define GST_CAT_DEFAULT pngenc_debug
/* Filter signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_SNAPSHOT TRUE
/* #define DEFAULT_NEWMEDIA FALSE */
#define DEFAULT_COMPRESSION_LEVEL 6
enum
{
ARG_0,
ARG_SNAPSHOT,
/* ARG_NEWMEDIA, */
ARG_COMPRESSION_LEVEL
};
static GstStaticPadTemplate pngenc_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/png, "
"width = (int) [ 16, 4096 ], "
"height = (int) [ 16, 4096 ], " "framerate = (fraction) [ 0.0, MAX ]")
);
static GstStaticPadTemplate pngenc_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBA ";" GST_VIDEO_CAPS_RGB)
);
/* static GstElementClass *parent_class = NULL; */
GST_BOILERPLATE (GstPngEnc, gst_pngenc, GstElement, GST_TYPE_ELEMENT);
static void gst_pngenc_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec);
static void gst_pngenc_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec);
static GstFlowReturn gst_pngenc_chain (GstPad * pad, GstBuffer * data);
static void
user_error_fn (png_structp png_ptr, png_const_charp error_msg)
{
g_warning ("%s", error_msg);
}
static void
user_warning_fn (png_structp png_ptr, png_const_charp warning_msg)
{
g_warning ("%s", warning_msg);
}
static void
gst_pngenc_base_init (gpointer g_class)
{
GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_add_pad_template
(element_class, gst_static_pad_template_get (&pngenc_sink_template));
gst_element_class_add_pad_template
(element_class, gst_static_pad_template_get (&pngenc_src_template));
gst_element_class_set_details (element_class, &gst_pngenc_details);
}
static void
gst_pngenc_class_init (GstPngEncClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
parent_class = g_type_class_peek_parent (klass);
gobject_class->get_property = gst_pngenc_get_property;
gobject_class->set_property = gst_pngenc_set_property;
g_object_class_install_property (gobject_class, ARG_SNAPSHOT,
g_param_spec_boolean ("snapshot", "Snapshot",
"Send EOS after encoding a frame, useful for snapshots",
DEFAULT_SNAPSHOT, (GParamFlags) G_PARAM_READWRITE));
/* g_object_class_install_property (gobject_class, ARG_NEWMEDIA, */
/* g_param_spec_boolean ("newmedia", "newmedia", */
/* "Send new media discontinuity after encoding each frame", */
/* DEFAULT_NEWMEDIA, (GParamFlags) G_PARAM_READWRITE)); */
g_object_class_install_property
(gobject_class, ARG_COMPRESSION_LEVEL,
g_param_spec_uint ("compression-level", "compression-level",
"PNG compression level",
Z_NO_COMPRESSION, Z_BEST_COMPRESSION,
DEFAULT_COMPRESSION_LEVEL, (GParamFlags) G_PARAM_READWRITE));
GST_DEBUG_CATEGORY_INIT (pngenc_debug, "pngenc", 0, "PNG image encoder");
}
static gboolean
gst_pngenc_setcaps (GstPad * pad, GstCaps * caps)
{
GstPngEnc *pngenc;
const GValue *fps;
GstStructure *structure;
GstCaps *pcaps;
gboolean ret = TRUE;
pngenc = GST_PNGENC (gst_pad_get_parent (pad));
structure = gst_caps_get_structure (caps, 0);
gst_structure_get_int (structure, "width", &pngenc->width);
gst_structure_get_int (structure, "height", &pngenc->height);
fps = gst_structure_get_value (structure, "framerate");
gst_structure_get_int (structure, "bpp", &pngenc->bpp);
if (pngenc->bpp == 32)
pngenc->stride = pngenc->width * 4;
else
pngenc->stride = GST_ROUND_UP_4 (pngenc->width * 3);
pcaps = gst_caps_new_simple ("image/png",
"width", G_TYPE_INT, pngenc->width,
"height", G_TYPE_INT, pngenc->height, NULL);
structure = gst_caps_get_structure (pcaps, 0);
gst_structure_set_value (structure, "framerate", fps);
ret = gst_pad_set_caps (pngenc->srcpad, pcaps);
gst_caps_unref (pcaps);
gst_object_unref (pngenc);
return ret;
}
static void
gst_pngenc_init (GstPngEnc * pngenc, GstPngEncClass * g_class)
{
/* sinkpad */
pngenc->sinkpad = gst_pad_new_from_static_template
(&pngenc_sink_template, "sink");
gst_pad_set_chain_function (pngenc->sinkpad, gst_pngenc_chain);
/* gst_pad_set_link_function (pngenc->sinkpad, gst_pngenc_sinklink); */
/* gst_pad_set_getcaps_function (pngenc->sinkpad, gst_pngenc_sink_getcaps); */
gst_pad_set_setcaps_function (pngenc->sinkpad, gst_pngenc_setcaps);
gst_element_add_pad (GST_ELEMENT (pngenc), pngenc->sinkpad);
/* srcpad */
pngenc->srcpad = gst_pad_new_from_static_template
(&pngenc_src_template, "src");
/* pngenc->srcpad = gst_pad_new ("src", GST_PAD_SRC); */
/* gst_pad_set_getcaps_function (pngenc->srcpad, gst_pngenc_src_getcaps); */
/* gst_pad_set_setcaps_function (pngenc->srcpad, gst_pngenc_setcaps); */
gst_element_add_pad (GST_ELEMENT (pngenc), pngenc->srcpad);
/* init settings */
pngenc->png_struct_ptr = NULL;
pngenc->png_info_ptr = NULL;
pngenc->snapshot = DEFAULT_SNAPSHOT;
/* pngenc->newmedia = FALSE; */
pngenc->compression_level = DEFAULT_COMPRESSION_LEVEL;
}
static void
user_flush_data (png_structp png_ptr G_GNUC_UNUSED)
{
}
static void
user_write_data (png_structp png_ptr, png_bytep data, png_uint_32 length)
{
GstPngEnc *pngenc;
pngenc = (GstPngEnc *) png_get_io_ptr (png_ptr);
if (pngenc->written + length >= GST_BUFFER_SIZE (pngenc->buffer_out)) {
GST_ERROR_OBJECT (pngenc, "output buffer bigger than the input buffer!?");
/* yuck */
longjmp (pngenc->png_struct_ptr->jmpbuf, 1);
/* never reached */
return;
}
memcpy (GST_BUFFER_DATA (pngenc->buffer_out) + pngenc->written, data, length);
pngenc->written += length;
}
static GstFlowReturn
gst_pngenc_chain (GstPad * pad, GstBuffer * buf)
{
GstPngEnc *pngenc;
gint row_index;
png_byte *row_pointers[MAX_HEIGHT];
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *encoded_buf = NULL;
pngenc = GST_PNGENC (gst_pad_get_parent (pad));
GST_DEBUG_OBJECT (pngenc, "BEGINNING");
/* initialize png struct stuff */
pngenc->png_struct_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING,
(png_voidp) NULL, user_error_fn, user_warning_fn);
if (pngenc->png_struct_ptr == NULL) {
gst_buffer_unref (buf);
GST_ELEMENT_ERROR (pngenc, LIBRARY, INIT, (NULL),
("Failed to initialize png structure"));
ret = GST_FLOW_ERROR;
goto done;
}
pngenc->png_info_ptr = png_create_info_struct (pngenc->png_struct_ptr);
if (!pngenc->png_info_ptr) {
gst_buffer_unref (buf);
png_destroy_write_struct (&(pngenc->png_struct_ptr), (png_infopp) NULL);
GST_ELEMENT_ERROR (pngenc, LIBRARY, INIT, (NULL),
("Failed to initialize the png info structure"));
ret = GST_FLOW_ERROR;
goto done;
}
/* non-0 return is from a longjmp inside of libpng */
if (setjmp (pngenc->png_struct_ptr->jmpbuf) != 0) {
gst_buffer_unref (buf);
png_destroy_write_struct (&pngenc->png_struct_ptr, &pngenc->png_info_ptr);
GST_ELEMENT_ERROR (pngenc, LIBRARY, FAILED, (NULL),
("returning from longjmp"));
ret = GST_FLOW_ERROR;
goto done;
}
png_set_filter (pngenc->png_struct_ptr, 0,
PNG_FILTER_NONE | PNG_FILTER_VALUE_NONE);
png_set_compression_level (pngenc->png_struct_ptr, pngenc->compression_level);
png_set_IHDR (pngenc->png_struct_ptr,
pngenc->png_info_ptr,
pngenc->width,
pngenc->height,
8,
(pngenc->bpp == 32) ? PNG_COLOR_TYPE_RGBA : PNG_COLOR_TYPE_RGB,
PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
png_set_write_fn (pngenc->png_struct_ptr, pngenc,
(png_rw_ptr) user_write_data, user_flush_data);
for (row_index = 0; row_index < pngenc->height; row_index++) {
row_pointers[row_index] = GST_BUFFER_DATA (buf) +
(row_index * pngenc->stride);
}
/* allocate the output buffer */
pngenc->buffer_out =
gst_buffer_new_and_alloc (pngenc->height * pngenc->stride);
pngenc->written = 0;
png_write_info (pngenc->png_struct_ptr, pngenc->png_info_ptr);
png_write_image (pngenc->png_struct_ptr, row_pointers);
png_write_end (pngenc->png_struct_ptr, NULL);
encoded_buf = gst_buffer_create_sub (pngenc->buffer_out, 0, pngenc->written);
png_destroy_info_struct (pngenc->png_struct_ptr, &pngenc->png_info_ptr);
png_destroy_write_struct (&pngenc->png_struct_ptr, (png_infopp) NULL);
gst_buffer_copy_metadata (encoded_buf, buf, GST_BUFFER_COPY_TIMESTAMPS);
gst_buffer_unref (buf);
gst_buffer_set_caps (encoded_buf, GST_PAD_CAPS (pngenc->srcpad));
if ((ret = gst_pad_push (pngenc->srcpad, encoded_buf)) != GST_FLOW_OK)
goto done;
if (pngenc->snapshot) {
GstEvent *event;
GST_DEBUG_OBJECT (pngenc, "snapshot mode, sending EOS");
/* send EOS event, since a frame has been pushed out */
event = gst_event_new_eos ();
gst_pad_push_event (pngenc->srcpad, event);
ret = GST_FLOW_UNEXPECTED;
}
done:
GST_DEBUG_OBJECT (pngenc, "END, ret:%d", ret);
if (pngenc->buffer_out != NULL) {
gst_buffer_unref (pngenc->buffer_out);
pngenc->buffer_out = NULL;
}
gst_object_unref (pngenc);
return ret;
}
static void
gst_pngenc_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstPngEnc *pngenc;
pngenc = GST_PNGENC (object);
switch (prop_id) {
case ARG_SNAPSHOT:
g_value_set_boolean (value, pngenc->snapshot);
break;
/* case ARG_NEWMEDIA: */
/* g_value_set_boolean (value, pngenc->newmedia); */
/* break; */
case ARG_COMPRESSION_LEVEL:
g_value_set_uint (value, pngenc->compression_level);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
static void
gst_pngenc_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstPngEnc *pngenc;
pngenc = GST_PNGENC (object);
switch (prop_id) {
case ARG_SNAPSHOT:
pngenc->snapshot = g_value_get_boolean (value);
break;
/* case ARG_NEWMEDIA: */
/* pngenc->newmedia = g_value_get_boolean (value); */
/* break; */
case ARG_COMPRESSION_LEVEL:
pngenc->compression_level = g_value_get_uint (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}