gstreamer/ext/libpng/gstpngdec.c
Julien Moutte 2b5cfd86cf ext/libpng/gstpngdec.c: Push a newsegment event, move some redundant code in a single place.
Original commit message from CVS:
2005-10-25  Julien MOUTTE  <julien@moutte.net>

* ext/libpng/gstpngdec.c: (user_info_callback),
(gst_pngdec_caps_create_and_set), (gst_pngdec_task): Push
a newsegment event, move some redundant code in a single place.
2005-10-25 10:47:09 +00:00

651 lines
17 KiB
C

/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* 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.
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gstpngdec.h"
#include <string.h>
#include <gst/video/video.h>
#include <gst/gst-i18n-plugin.h>
static GstElementDetails gst_pngdec_details = {
"PNG decoder",
"Codec/Decoder/Image",
"Decode a png video frame to a raw image",
"Wim Taymans <wim@fluendo.com>",
};
GST_DEBUG_CATEGORY (pngdec_debug);
#define GST_CAT_DEFAULT pngdec_debug
static void gst_pngdec_base_init (gpointer g_class);
static void gst_pngdec_class_init (GstPngDecClass * klass);
static void gst_pngdec_init (GstPngDec * pngdec);
static gboolean gst_pngdec_libpng_init (GstPngDec * pngdec);
static gboolean gst_pngdec_libpng_clear (GstPngDec * pngdec);
static GstStateChangeReturn gst_pngdec_change_state (GstElement * element,
GstStateChange transition);
static gboolean gst_pngdec_sink_activate_push (GstPad * sinkpad,
gboolean active);
static gboolean gst_pngdec_sink_activate_pull (GstPad * sinkpad,
gboolean active);
static gboolean gst_pngdec_sink_activate (GstPad * sinkpad);
static GstFlowReturn gst_pngdec_caps_create_and_set (GstPngDec * pngdec);
static void gst_pngdec_task (GstPad * pad);
static GstFlowReturn gst_pngdec_chain (GstPad * pad, GstBuffer * buffer);
static gboolean gst_pngdec_sink_event (GstPad * pad, GstEvent * event);
static GstElementClass *parent_class = NULL;
GType
gst_pngdec_get_type (void)
{
static GType pngdec_type = 0;
if (!pngdec_type) {
static const GTypeInfo pngdec_info = {
sizeof (GstPngDecClass),
gst_pngdec_base_init,
NULL,
(GClassInitFunc) gst_pngdec_class_init,
NULL,
NULL,
sizeof (GstPngDec),
0,
(GInstanceInitFunc) gst_pngdec_init,
};
pngdec_type = g_type_register_static (GST_TYPE_ELEMENT, "GstPngDec",
&pngdec_info, 0);
}
return pngdec_type;
}
static GstStaticPadTemplate gst_pngdec_src_pad_template =
GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC,
GST_PAD_ALWAYS,
GST_STATIC_CAPS (GST_VIDEO_CAPS_RGBA ";" GST_VIDEO_CAPS_RGB)
);
static GstStaticPadTemplate gst_pngdec_sink_pad_template =
GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS ("image/png")
);
static void
gst_pngdec_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 (&gst_pngdec_src_pad_template));
gst_element_class_add_pad_template (element_class,
gst_static_pad_template_get (&gst_pngdec_sink_pad_template));
gst_element_class_set_details (element_class, &gst_pngdec_details);
}
static void
gst_pngdec_class_init (GstPngDecClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *gstelement_class;
gobject_class = (GObjectClass *) klass;
gstelement_class = (GstElementClass *) klass;
parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
gstelement_class->change_state = gst_pngdec_change_state;
GST_DEBUG_CATEGORY_INIT (pngdec_debug, "pngdec", 0, "PNG image decoder");
}
static void
gst_pngdec_init (GstPngDec * pngdec)
{
pngdec->sinkpad = gst_pad_new_from_template (gst_static_pad_template_get
(&gst_pngdec_sink_pad_template), "sink");
gst_pad_set_activate_function (pngdec->sinkpad, gst_pngdec_sink_activate);
gst_pad_set_activatepush_function (pngdec->sinkpad,
gst_pngdec_sink_activate_push);
gst_pad_set_activatepull_function (pngdec->sinkpad,
gst_pngdec_sink_activate_pull);
gst_pad_set_chain_function (pngdec->sinkpad, gst_pngdec_chain);
gst_pad_set_event_function (pngdec->sinkpad, gst_pngdec_sink_event);
gst_element_add_pad (GST_ELEMENT (pngdec), pngdec->sinkpad);
pngdec->srcpad = gst_pad_new_from_template (gst_static_pad_template_get
(&gst_pngdec_src_pad_template), "src");
gst_pad_use_fixed_caps (pngdec->srcpad);
gst_element_add_pad (GST_ELEMENT (pngdec), pngdec->srcpad);
/* gst_pad_set_chain_function (pngdec->sinkpad, gst_pngdec_chain); */
pngdec->buffer_out = NULL;
pngdec->png = NULL;
pngdec->info = NULL;
pngdec->endinfo = NULL;
pngdec->setup = FALSE;
pngdec->color_type = -1;
pngdec->width = -1;
pngdec->height = -1;
pngdec->bpp = -1;
pngdec->fps = 0.0;
}
static void
user_error_fn (png_structp png_ptr, png_const_charp error_msg)
{
GST_ERROR ("%s", error_msg);
}
static void
user_warning_fn (png_structp png_ptr, png_const_charp warning_msg)
{
GST_WARNING ("%s", warning_msg);
}
static void
user_info_callback (png_structp png_ptr, png_infop info)
{
GstPngDec *pngdec = NULL;
GstFlowReturn ret = GST_FLOW_OK;
size_t buffer_size;
GstBuffer *buffer = NULL;
pngdec = GST_PNGDEC (png_ptr->io_ptr);
GST_LOG ("info ready");
/* Generate the caps and configure */
ret = gst_pngdec_caps_create_and_set (pngdec);
if (ret != GST_FLOW_OK) {
goto beach;
}
/* Allocate output buffer */
pngdec->rowbytes = png_get_rowbytes (pngdec->png, pngdec->info);
buffer_size = pngdec->height * GST_ROUND_UP_4 (pngdec->rowbytes);
ret = gst_pad_alloc_buffer (pngdec->srcpad, GST_BUFFER_OFFSET_NONE,
buffer_size, GST_PAD_CAPS (pngdec->srcpad), &buffer);
if (ret != GST_FLOW_OK) {
goto beach;
}
pngdec->buffer_out = buffer;
beach:
pngdec->ret = ret;
}
static void
user_endrow_callback (png_structp png_ptr, png_bytep new_row,
png_uint_32 row_num, int pass)
{
GstPngDec *pngdec = NULL;
pngdec = GST_PNGDEC (png_ptr->io_ptr);
/* FIXME: implement interlaced pictures */
if (GST_IS_BUFFER (pngdec->buffer_out)) {
size_t offset = row_num * GST_ROUND_UP_4 (pngdec->rowbytes);
GST_LOG ("got row %d, copying in buffer %p at offset %d", row_num,
pngdec->buffer_out, offset);
memcpy (GST_BUFFER_DATA (pngdec->buffer_out) + offset, new_row,
pngdec->rowbytes);
pngdec->ret = GST_FLOW_OK;
} else {
GST_LOG ("we don't have any output buffer to write this row !");
pngdec->ret = GST_FLOW_ERROR;
}
}
static void
user_end_callback (png_structp png_ptr, png_infop info)
{
GstPngDec *pngdec = NULL;
pngdec = GST_PNGDEC (png_ptr->io_ptr);
GST_LOG ("and we are done reading this image, pushing it and setting eos");
/* Push our buffer and then EOS */
pngdec->ret = gst_pad_push (pngdec->srcpad, pngdec->buffer_out);
pngdec->ret = gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
}
static void
user_read_data (png_structp png_ptr, png_bytep data, png_size_t length)
{
GstPngDec *pngdec;
GstBuffer *buffer;
GstFlowReturn ret = GST_FLOW_OK;
pngdec = GST_PNGDEC (png_ptr->io_ptr);
GST_LOG ("reading %d bytes of data at offset %d", length, pngdec->offset);
ret = gst_pad_pull_range (pngdec->sinkpad, pngdec->offset, length, &buffer);
if ((ret != GST_FLOW_OK) || (GST_BUFFER_SIZE (buffer) != length))
goto pause;
memcpy (data, GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer));
gst_buffer_unref (buffer);
pngdec->offset += length;
return;
pause:
GST_LOG_OBJECT (pngdec, "pausing task, reason %s", gst_flow_get_name (ret));
gst_pad_pause_task (pngdec->sinkpad);
if (GST_FLOW_IS_FATAL (ret)) {
gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
GST_ELEMENT_ERROR (pngdec, STREAM, FAILED,
(_("Internal data stream error.")),
("stream stopped, reason %s", gst_flow_get_name (ret)));
}
}
static GstFlowReturn
gst_pngdec_caps_create_and_set (GstPngDec * pngdec)
{
GstFlowReturn ret = GST_FLOW_OK;
GstCaps *caps = NULL, *res = NULL;
GstPadTemplate *templ = NULL;
GstEvent *new_seg = NULL;
gint bpc = 0, color_type;
png_uint_32 width, height;
g_return_val_if_fail (GST_IS_PNGDEC (pngdec), GST_FLOW_ERROR);
/* Get bits per channel */
bpc = png_get_bit_depth (pngdec->png, pngdec->info);
/* We don't handle 16 bits per color, strip down to 8 */
if (bpc == 16) {
GST_LOG ("this is a 16 bits per channel PNG image, strip down to 8 bits");
png_set_strip_16 (pngdec->png);
}
/* Get Color type */
color_type = png_get_color_type (pngdec->png, pngdec->info);
/* HACK: The doc states that it's RGBA but apparently it's not... */
if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
png_set_bgr (pngdec->png);
/* Update the info structure */
png_read_update_info (pngdec->png, pngdec->info);
/* Get IHDR header again after transformation settings */
png_get_IHDR (pngdec->png, pngdec->info, &width, &height,
&bpc, &pngdec->color_type, NULL, NULL, NULL);
pngdec->width = width;
pngdec->height = height;
GST_LOG ("this is a %dx%d PNG image", pngdec->width, pngdec->height);
switch (pngdec->color_type) {
case PNG_COLOR_TYPE_RGB:
GST_LOG ("we have no alpha channel, depth is 24 bits");
pngdec->bpp = 24;
break;
case PNG_COLOR_TYPE_RGB_ALPHA:
GST_LOG ("we have an alpha channel, depth is 32 bits");
pngdec->bpp = 32;
break;
default:
GST_ELEMENT_ERROR (pngdec, STREAM, NOT_IMPLEMENTED, (NULL),
("pngdec does not support grayscale or paletted data yet"));
ret = GST_FLOW_ERROR;
goto beach;
}
caps = gst_caps_new_simple ("video/x-raw-rgb",
"width", G_TYPE_INT, pngdec->width,
"height", G_TYPE_INT, pngdec->height,
"bpp", G_TYPE_INT, pngdec->bpp,
"framerate", G_TYPE_DOUBLE, pngdec->fps, NULL);
templ = gst_static_pad_template_get (&gst_pngdec_src_pad_template);
res = gst_caps_intersect (caps, gst_pad_template_get_caps (templ));
gst_caps_unref (caps);
if (!gst_pad_set_caps (pngdec->srcpad, res)) {
ret = GST_FLOW_ERROR;
}
GST_DEBUG_OBJECT (pngdec, "our caps %" GST_PTR_FORMAT, res);
gst_caps_unref (res);
/* Push a newsegment event */
new_seg = gst_event_new_newsegment (FALSE, 1.0, GST_FORMAT_TIME, 0, -1, 0);
if (GST_IS_EVENT (new_seg)) {
gst_pad_push_event (pngdec->srcpad, new_seg);
}
beach:
return ret;
}
static void
gst_pngdec_task (GstPad * pad)
{
GstPngDec *pngdec;
GstBuffer *buffer = NULL;
size_t buffer_size = 0;
gint i = 0;
png_bytep *rows, inp;
png_uint_32 rowbytes;
GstFlowReturn ret = GST_FLOW_OK;
pngdec = GST_PNGDEC (GST_OBJECT_PARENT (pad));
/* Let libpng come back here on error */
if (setjmp (png_jmpbuf (pngdec->png))) {
ret = GST_FLOW_ERROR;
goto pause;
}
/* Set reading callback */
png_set_read_fn (pngdec->png, pngdec, user_read_data);
/* Read info */
png_read_info (pngdec->png, pngdec->info);
/* Generate the caps and configure */
ret = gst_pngdec_caps_create_and_set (pngdec);
if (ret != GST_FLOW_OK) {
goto pause;
}
/* Allocate output buffer */
rowbytes = png_get_rowbytes (pngdec->png, pngdec->info);
buffer_size = pngdec->height * GST_ROUND_UP_4 (rowbytes);
ret = gst_pad_alloc_buffer (pngdec->srcpad, GST_BUFFER_OFFSET_NONE,
buffer_size, GST_PAD_CAPS (pngdec->srcpad), &buffer);
if (ret != GST_FLOW_OK) {
goto pause;
}
rows = (png_bytep *) g_malloc (sizeof (png_bytep) * pngdec->height);
inp = GST_BUFFER_DATA (buffer);
for (i = 0; i < pngdec->height; i++) {
rows[i] = inp;
inp += GST_ROUND_UP_4 (rowbytes);
}
/* Read the actual picture */
png_read_image (pngdec->png, rows);
free (rows);
/* Push the raw RGB frame */
ret = gst_pad_push (pngdec->srcpad, buffer);
if (ret != GST_FLOW_OK) {
goto pause;
}
/* And we are done */
gst_pad_pause_task (pngdec->sinkpad);
gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
return;
pause:
GST_LOG_OBJECT (pngdec, "pausing task, reason %s", gst_flow_get_name (ret));
gst_pad_pause_task (pngdec->sinkpad);
if (GST_FLOW_IS_FATAL (ret)) {
gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
GST_ELEMENT_ERROR (pngdec, STREAM, FAILED,
(_("Internal data stream error.")),
("stream stopped, reason %s", gst_flow_get_name (ret)));
}
}
static GstFlowReturn
gst_pngdec_chain (GstPad * pad, GstBuffer * buffer)
{
GstPngDec *pngdec;
GstFlowReturn ret = GST_FLOW_OK;
pngdec = GST_PNGDEC (GST_OBJECT_PARENT (pad));
if (!pngdec->setup) {
GST_LOG ("we are not configured yet");
ret = GST_FLOW_WRONG_STATE;
goto beach;
}
/* Something is going wrong in our callbacks */
if (pngdec->ret != GST_FLOW_OK) {
ret = pngdec->ret;
goto beach;
}
/* Let libpng come back here on error */
if (setjmp (png_jmpbuf (pngdec->png))) {
ret = GST_FLOW_ERROR;
goto beach;
}
/* Progressive loading of the PNG image */
png_process_data (pngdec->png, pngdec->info, GST_BUFFER_DATA (buffer),
GST_BUFFER_SIZE (buffer));
/* And release the buffer */
gst_buffer_unref (buffer);
beach:
return ret;
}
static gboolean
gst_pngdec_sink_event (GstPad * pad, GstEvent * event)
{
GstPngDec *pngdec;
pngdec = GST_PNGDEC (GST_OBJECT_PARENT (pad));
switch (GST_EVENT_TYPE (event)) {
case GST_EVENT_EOS:
gst_pngdec_libpng_clear (pngdec);
default:
return gst_pad_event_default (pad, event);
}
}
/* Clean up the libpng structures */
static gboolean
gst_pngdec_libpng_clear (GstPngDec * pngdec)
{
png_infopp info = NULL, endinfo = NULL;
g_return_val_if_fail (GST_IS_PNGDEC (pngdec), FALSE);
GST_LOG ("cleaning up libpng structures");
if (pngdec->info) {
info = &pngdec->info;
}
if (pngdec->endinfo) {
endinfo = &pngdec->endinfo;
}
if (pngdec->png) {
png_destroy_read_struct (&(pngdec->png), info, endinfo);
pngdec->png = NULL;
pngdec->info = NULL;
pngdec->endinfo = NULL;
}
pngdec->bpp = pngdec->color_type = pngdec->height = pngdec->width = -1;
pngdec->offset = 0;
pngdec->rowbytes = 0;
pngdec->buffer_out = NULL;
pngdec->setup = FALSE;
return TRUE;
}
static gboolean
gst_pngdec_libpng_init (GstPngDec * pngdec)
{
g_return_val_if_fail (GST_IS_PNGDEC (pngdec), FALSE);
if (pngdec->setup) {
goto beach;
}
/* initialize png struct stuff */
pngdec->png = png_create_read_struct (PNG_LIBPNG_VER_STRING,
(png_voidp) NULL, user_error_fn, user_warning_fn);
if (pngdec->png == NULL) {
GST_ELEMENT_ERROR (pngdec, LIBRARY, INIT, (NULL),
("Failed to initialize png structure"));
goto beach;
}
pngdec->info = png_create_info_struct (pngdec->png);
if (pngdec->info == NULL) {
gst_pngdec_libpng_clear (pngdec);
GST_ELEMENT_ERROR (pngdec, LIBRARY, INIT, (NULL),
("Failed to initialize info structure"));
goto beach;
}
pngdec->endinfo = png_create_info_struct (pngdec->png);
if (pngdec->endinfo == NULL) {
gst_pngdec_libpng_clear (pngdec);
GST_ELEMENT_ERROR (pngdec, LIBRARY, INIT, (NULL),
("Failed to initialize endinfo structure"));
goto beach;
}
pngdec->setup = TRUE;
beach:
return pngdec->setup;
}
static GstStateChangeReturn
gst_pngdec_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_FAILURE;
GstPngDec *pngdec = NULL;
pngdec = GST_PNGDEC (element);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_PAUSED:
gst_pngdec_libpng_init (pngdec);
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
gst_pngdec_libpng_clear (pngdec);
break;
default:
break;
}
ret = parent_class->change_state (element, transition);
return ret;
}
/* this function gets called when we activate ourselves in push mode. */
static gboolean
gst_pngdec_sink_activate_push (GstPad * sinkpad, gboolean active)
{
GstPngDec *pngdec;
pngdec = GST_PNGDEC (GST_OBJECT_PARENT (sinkpad));
pngdec->ret = GST_FLOW_OK;
if (active) {
/* Let libpng come back here on error */
if (setjmp (png_jmpbuf (pngdec->png))) {
GST_LOG ("failed setting up libpng jumb");
gst_pngdec_libpng_clear (pngdec);
return FALSE;
}
GST_LOG ("setting up progressive loading callbacks");
png_set_progressive_read_fn (pngdec->png, pngdec,
user_info_callback, user_endrow_callback, user_end_callback);
}
return TRUE;
}
/* this function gets called when we activate ourselves in pull mode.
* We can perform random access to the resource and we start a task
* to start reading */
static gboolean
gst_pngdec_sink_activate_pull (GstPad * sinkpad, gboolean active)
{
GstPngDec *pngdec;
pngdec = GST_PNGDEC (GST_OBJECT_PARENT (sinkpad));
if (active) {
return gst_pad_start_task (sinkpad, (GstTaskFunction) gst_pngdec_task,
sinkpad);
} else {
return gst_pad_stop_task (sinkpad);
}
}
/* this function is called when the pad is activated and should start
* processing data.
*
* We check if we can do random access to decide if we work push or
* pull based.
*/
static gboolean
gst_pngdec_sink_activate (GstPad * sinkpad)
{
if (gst_pad_check_pull_range (sinkpad)) {
return gst_pad_activate_pull (sinkpad, TRUE);
} else {
return gst_pad_activate_push (sinkpad, TRUE);
}
}