gstreamer/ext/libpng/gstpngenc.c
Mark Nauwelaerts a31a9e1f33 pngenc: disably snapshot behaviour by default
... since such behaviour is not consistent, if allowable at all.
2012-01-24 18:25:04 +01:00

456 lines
12 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 <zlib.h>
GST_DEBUG_CATEGORY_STATIC (pngenc_debug);
#define GST_CAT_DEFAULT pngenc_debug
/* Filter signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_SNAPSHOT FALSE
/* #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, 1000000 ], "
"height = (int) [ 16, 1000000 ], " "framerate = " GST_VIDEO_FPS_RANGE)
);
static GstStaticPadTemplate pngenc_sink_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_MAKE ("{ RGBA, RGB, GRAY8 }"))
);
/* static GstElementClass *parent_class = NULL; */
G_DEFINE_TYPE (GstPngEnc, gst_pngenc, 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, GstObject * parent,
GstBuffer * data);
static gboolean gst_pngenc_sink_event (GstPad * pad, GstObject * parent,
GstEvent * event);
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_class_init (GstPngEncClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *element_class;
gobject_class = (GObjectClass *) klass;
element_class = (GstElementClass *) 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, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/* 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, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); */
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,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
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_simple (element_class, "PNG image encoder",
"Codec/Encoder/Image",
"Encode a video frame to a .png image",
"Jeremy SIMON <jsimon13@yahoo.fr>");
GST_DEBUG_CATEGORY_INIT (pngenc_debug, "pngenc", 0, "PNG image encoder");
}
static gboolean
gst_pngenc_setcaps (GstPngEnc * pngenc, GstCaps * caps)
{
int fps_n, fps_d;
GstCaps *pcaps;
gboolean ret;
GstVideoInfo info;
ret = gst_video_info_from_caps (&info, caps);
if (G_UNLIKELY (!ret))
goto done;
pngenc->info = info;
switch (GST_VIDEO_INFO_FORMAT (&info)) {
case GST_VIDEO_FORMAT_RGBA:
pngenc->png_color_type = PNG_COLOR_TYPE_RGBA;
break;
case GST_VIDEO_FORMAT_RGB:
pngenc->png_color_type = PNG_COLOR_TYPE_RGB;
break;
case GST_VIDEO_FORMAT_GRAY8:
pngenc->png_color_type = PNG_COLOR_TYPE_GRAY;
break;
default:
ret = FALSE;
goto done;
}
pngenc->width = GST_VIDEO_INFO_WIDTH (&info);
pngenc->height = GST_VIDEO_INFO_HEIGHT (&info);
fps_n = GST_VIDEO_INFO_FPS_N (&info);
fps_d = GST_VIDEO_INFO_FPS_D (&info);
if (G_UNLIKELY (pngenc->width < 16 || pngenc->width > 1000000 ||
pngenc->height < 16 || pngenc->height > 1000000)) {
ret = FALSE;
goto done;
}
pcaps = gst_caps_new_simple ("image/png",
"width", G_TYPE_INT, pngenc->width,
"height", G_TYPE_INT, pngenc->height,
"framerate", GST_TYPE_FRACTION, fps_n, fps_d, NULL);
ret = gst_pad_set_caps (pngenc->srcpad, pcaps);
gst_caps_unref (pcaps);
/* Fall-through. */
done:
if (G_UNLIKELY (!ret)) {
pngenc->width = 0;
pngenc->height = 0;
}
return ret;
}
static void
gst_pngenc_init (GstPngEnc * pngenc)
{
/* sinkpad */
pngenc->sinkpad = gst_pad_new_from_static_template
(&pngenc_sink_template, "sink");
gst_pad_set_chain_function (pngenc->sinkpad,
GST_DEBUG_FUNCPTR (gst_pngenc_chain));
gst_pad_set_event_function (pngenc->sinkpad,
GST_DEBUG_FUNCPTR (gst_pngenc_sink_event));
gst_element_add_pad (GST_ELEMENT (pngenc), pngenc->sinkpad);
/* srcpad */
pngenc->srcpad = gst_pad_new_from_static_template
(&pngenc_src_template, "src");
gst_pad_use_fixed_caps (pngenc->srcpad);
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;
gsize size;
guint8 *bdata;
pngenc = (GstPngEnc *) png_get_io_ptr (png_ptr);
bdata = gst_buffer_map (pngenc->buffer_out, &size, NULL, GST_MAP_WRITE);
if (pngenc->written + length >= size) {
gst_buffer_unmap (pngenc->buffer_out, data, -1);
GST_ERROR_OBJECT (pngenc, "output buffer bigger than the input buffer!?");
png_error (png_ptr, "output buffer bigger than the input buffer!?");
/* never reached */
return;
}
GST_DEBUG_OBJECT (pngenc, "writing %u bytes", (guint) length);
memcpy (bdata + pngenc->written, data, length);
gst_buffer_unmap (pngenc->buffer_out, data, -1);
pngenc->written += length;
}
static GstFlowReturn
gst_pngenc_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
{
GstPngEnc *pngenc;
gint row_index;
png_byte **row_pointers;
GstFlowReturn ret = GST_FLOW_OK;
GstBuffer *encoded_buf = NULL;
GstVideoFrame frame;
pngenc = GST_PNGENC (parent);
GST_DEBUG_OBJECT (pngenc, "BEGINNING");
if (G_UNLIKELY (pngenc->width <= 0 || pngenc->height <= 0)) {
ret = GST_FLOW_NOT_NEGOTIATED;
goto exit;
}
if (!gst_video_frame_map (&frame, &pngenc->info, buf, GST_MAP_READ)) {
GST_ELEMENT_ERROR (pngenc, STREAM, FORMAT, (NULL),
("Failed to map video frame, caps problem?"));
ret = GST_FLOW_ERROR;
goto exit;
}
/* 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_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) {
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 (png_jmpbuf (pngenc->png_struct_ptr)) != 0) {
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->png_color_type,
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);
row_pointers = g_new (png_byte *, pngenc->height);
for (row_index = 0; row_index < pngenc->height; row_index++) {
row_pointers[row_index] = GST_VIDEO_FRAME_COMP_DATA (&frame, 0) +
(row_index * GST_VIDEO_FRAME_COMP_STRIDE (&frame, 0));
}
/* allocate the output buffer */
pngenc->buffer_out =
gst_buffer_new_and_alloc (pngenc->height * pngenc->width);
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);
g_free (row_pointers);
GST_DEBUG_OBJECT (pngenc, "written %d", pngenc->written);
encoded_buf =
gst_buffer_copy_region (pngenc->buffer_out, GST_BUFFER_COPY_MEMORY,
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_TIMESTAMP (encoded_buf) = GST_BUFFER_TIMESTAMP (buf);
GST_BUFFER_DURATION (encoded_buf) = GST_BUFFER_DURATION (buf);
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_EOS;
}
done:
gst_video_frame_unmap (&frame);
exit:
gst_buffer_unref (buf);
GST_DEBUG_OBJECT (pngenc, "END, ret:%d", ret);
if (pngenc->buffer_out != NULL) {
gst_buffer_unref (pngenc->buffer_out);
pngenc->buffer_out = NULL;
}
return ret;
}
static gboolean
gst_pngenc_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
{
GstPngEnc *enc;
gboolean res;
enc = GST_PNGENC (parent);
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_CAPS:
{
GstCaps *caps;
gst_event_parse_caps (event, &caps);
res = gst_pngenc_setcaps (enc, caps);
gst_event_unref (event);
break;
}
default:
res = gst_pad_push_event (enc->srcpad, event);
break;
}
return res;
}
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;
}
}