gstreamer/ext/cairo/gstcairorender.c
2012-04-10 00:51:41 +01:00

383 lines
10 KiB
C

/* GStreamer
*
* Copyright (C) 2006-2009 Lutz Mueller <lutz@topfrose.de>
*
* 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.
*/
/**
* SECTION:element-cairorender
*
* cairorender encodes a video stream into PDF, SVG, PNG or Postscript
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch videotestsrc num-buffers=3 ! cairorender ! "application/pdf" ! filesink location=test.pdf
* ]|
* </refsect2>
*/
#include "gstcairorender.h"
#include <cairo.h>
#include <cairo-features.h>
#ifdef CAIRO_HAS_PS_SURFACE
#include <cairo-ps.h>
#endif
#ifdef CAIRO_HAS_PDF_SURFACE
#include <cairo-pdf.h>
#endif
#ifdef CAIRO_HAS_SVG_SURFACE
#include <cairo-svg.h>
#endif
#include <gst/video/video.h>
#include <string.h>
GST_DEBUG_CATEGORY_STATIC (cairo_render_debug);
#define GST_CAT_DEFAULT cairo_render_debug
static gboolean
gst_cairo_render_event (GstPad * pad, GstEvent * e)
{
GstCairoRender *c = GST_CAIRO_RENDER (GST_PAD_PARENT (pad));
switch (GST_EVENT_TYPE (e)) {
case GST_EVENT_EOS:
if (c->surface)
cairo_surface_finish (c->surface);
break;
default:
break;
}
return gst_pad_event_default (pad, e);
}
static cairo_status_t
write_func (void *closure, const unsigned char *data, unsigned int length)
{
GstCairoRender *c = GST_CAIRO_RENDER (closure);
GstBuffer *buf;
GstFlowReturn r;
buf = gst_buffer_new ();
gst_buffer_set_data (buf, (guint8 *) data, length);
gst_buffer_set_caps (buf, GST_PAD_CAPS (c->src));
if ((r = gst_pad_push (c->src, buf)) != GST_FLOW_OK) {
GST_DEBUG_OBJECT (c, "Could not pass on buffer: %s.",
gst_flow_get_name (r));
return CAIRO_STATUS_WRITE_ERROR;
}
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
read_buffer (void *closure, unsigned char *data, unsigned int length)
{
GstBuffer *buf = GST_BUFFER (closure);
if (GST_BUFFER_OFFSET (buf) + length > GST_BUFFER_SIZE (buf))
return CAIRO_STATUS_READ_ERROR;
memcpy (data, GST_BUFFER_DATA (buf) + GST_BUFFER_OFFSET (buf), length);
GST_BUFFER_OFFSET (buf) += length;
return CAIRO_STATUS_SUCCESS;
}
static gboolean
gst_cairo_render_push_surface (GstCairoRender * c, cairo_surface_t * surface)
{
cairo_status_t s = 0;
cairo_t *cr;
if (!c->surface) {
s = cairo_surface_write_to_png_stream (surface, write_func, c);
cairo_surface_destroy (surface);
if (s != CAIRO_STATUS_SUCCESS) {
GST_DEBUG_OBJECT (c, "Could not create PNG stream: %s.",
cairo_status_to_string (s));
return FALSE;
}
return TRUE;
}
cr = cairo_create (c->surface);
cairo_set_source_surface (cr, surface, 0, 0);
cairo_paint (cr);
cairo_show_page (cr);
cairo_destroy (cr);
cairo_surface_destroy (surface);
return (TRUE);
}
static GstFlowReturn
gst_cairo_render_chain (GstPad * pad, GstBuffer * buf)
{
GstCairoRender *c = GST_CAIRO_RENDER (GST_PAD_PARENT (pad));
cairo_surface_t *s;
gboolean success;
if (G_UNLIKELY (c->width <= 0 || c->height <= 0 || c->stride <= 0))
return GST_FLOW_NOT_NEGOTIATED;
if (c->png) {
GST_BUFFER_OFFSET (buf) = 0;
s = cairo_image_surface_create_from_png_stream (read_buffer, buf);
} else {
if (c->format == CAIRO_FORMAT_ARGB32) {
guint i, j;
guint8 *data = GST_BUFFER_DATA (buf);
buf = gst_buffer_make_writable (buf);
/* Cairo ARGB is pre-multiplied with the alpha
* value, i.e. 0x80008000 is half transparent
* green
*/
for (i = 0; i < c->height; i++) {
for (j = 0; j < c->width; j++) {
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
guint8 alpha = data[3];
data[0] = (data[0] * alpha) >> 8;
data[1] = (data[1] * alpha) >> 8;
data[2] = (data[2] * alpha) >> 8;
#else
guint8 alpha = data[0];
data[1] = (data[1] * alpha) >> 8;
data[2] = (data[2] * alpha) >> 8;
data[3] = (data[3] * alpha) >> 8;
#endif
data += 4;
}
}
}
s = cairo_image_surface_create_for_data (GST_BUFFER_DATA (buf),
c->format, c->width, c->height, c->stride);
}
success = gst_cairo_render_push_surface (c, s);
gst_buffer_unref (buf);
return success ? GST_FLOW_OK : GST_FLOW_ERROR;
}
static gboolean
gst_cairo_render_setcaps_sink (GstPad * pad, GstCaps * caps)
{
GstCairoRender *c = GST_CAIRO_RENDER (GST_PAD_PARENT (pad));
GstStructure *s = gst_caps_get_structure (caps, 0);
const gchar *mime = gst_structure_get_name (s);
gint fps_n = 0, fps_d = 1;
gint w, h;
GST_DEBUG_OBJECT (c, "Got caps (%s).", mime);
if ((c->png = !strcmp (mime, "image/png")))
return TRUE;
/* Width and height */
if (!gst_structure_get_int (s, "width", &c->width) ||
!gst_structure_get_int (s, "height", &c->height)) {
GST_ERROR_OBJECT (c, "Invalid caps");
return FALSE;
}
/* Colorspace */
if (!strcmp (mime, "video/x-raw-yuv") || !strcmp (mime, "video/x-raw-grey")) {
c->format = CAIRO_FORMAT_A8;
c->stride = GST_ROUND_UP_4 (c->width);
} else if (!strcmp (mime, "video/x-raw-rgb")) {
gint bpp;
if (!gst_structure_get_int (s, "bpp", &bpp)) {
GST_ERROR_OBJECT (c, "Invalid caps");
return FALSE;
}
c->format = (bpp == 32) ? CAIRO_FORMAT_ARGB32 : CAIRO_FORMAT_RGB24;
c->stride = 4 * c->width;
} else {
GST_DEBUG_OBJECT (c, "Unknown mime type '%s'.", mime);
return FALSE;
}
/* Framerate */
gst_structure_get_fraction (s, "framerate", &fps_n, &fps_d);
/* Create output caps */
caps = gst_pad_get_allowed_caps (c->src);
caps = gst_caps_make_writable (caps);
gst_caps_truncate (caps);
s = gst_caps_get_structure (caps, 0);
mime = gst_structure_get_name (s);
gst_structure_set (s, "height", G_TYPE_INT, c->height, "width", G_TYPE_INT,
c->width, "framerate", GST_TYPE_FRACTION, fps_n, fps_d, NULL);
if (c->surface) {
cairo_surface_destroy (c->surface);
c->surface = NULL;
}
w = c->width;
h = c->height;
GST_DEBUG_OBJECT (c, "Setting src caps %" GST_PTR_FORMAT, caps);
gst_pad_set_caps (c->src, caps);
#if CAIRO_HAS_PS_SURFACE
if (!strcmp (mime, "application/postscript")) {
c->surface = cairo_ps_surface_create_for_stream (write_func, c, w, h);
} else
#endif
#if CAIRO_HAS_PDF_SURFACE
if (!strcmp (mime, "application/pdf")) {
c->surface = cairo_pdf_surface_create_for_stream (write_func, c, w, h);
} else
#endif
#if CAIRO_HAS_SVG_SURFACE
if (!strcmp (mime, "image/svg+xml")) {
c->surface = cairo_svg_surface_create_for_stream (write_func, c, w, h);
} else
#endif
{
gst_caps_unref (caps);
return FALSE;
}
gst_caps_unref (caps);
return TRUE;
}
#define SIZE_CAPS "width = (int) [ 1, MAX], height = (int) [ 1, MAX] "
#if CAIRO_HAS_PDF_SURFACE
#define PDF_CAPS "application/pdf, " SIZE_CAPS
#else
#define PDF_CAPS
#endif
#if CAIRO_HAS_PDF_SURFACE && (CAIRO_HAS_PS_SURFACE || CAIRO_HAS_SVG_SURFACE || CAIRO_HAS_PNG_FUNCTIONS)
#define JOIN1 ";"
#else
#define JOIN1
#endif
#if CAIRO_HAS_PS_SURFACE
#define PS_CAPS "application/postscript, " SIZE_CAPS
#else
#define PS_CAPS
#endif
#if (CAIRO_HAS_PDF_SURFACE || CAIRO_HAS_PS_SURFACE) && (CAIRO_HAS_SVG_SURFACE || CAIRO_HAS_PNG_FUNCTIONS)
#define JOIN2 ";"
#else
#define JOIN2
#endif
#if CAIRO_HAS_SVG_SURFACE
#define SVG_CAPS "image/svg+xml, " SIZE_CAPS
#else
#define SVG_CAPS
#endif
#if (CAIRO_HAS_PDF_SURFACE || CAIRO_HAS_PS_SURFACE || CAIRO_HAS_SVG_SURFACE) && CAIRO_HAS_PNG_FUNCTIONS
#define JOIN3 ";"
#else
#define JOIN3
#endif
#if CAIRO_HAS_PNG_FUNCTIONS
#define PNG_CAPS "image/png, " SIZE_CAPS
#define PNG_CAPS2 "; image/png, " SIZE_CAPS
#else
#define PNG_CAPS
#define PNG_CAPS2
#endif
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
#define ARGB_CAPS GST_VIDEO_CAPS_BGRx " ; " GST_VIDEO_CAPS_BGRA " ; "
#else
#define ARGB_CAPS GST_VIDEO_CAPS_xRGB " ; " GST_VIDEO_CAPS_ARGB " ; "
#endif
static GstStaticPadTemplate t_src = GST_STATIC_PAD_TEMPLATE ("src",
GST_PAD_SRC, GST_PAD_ALWAYS,
GST_STATIC_CAPS (PDF_CAPS JOIN1 PS_CAPS JOIN2 SVG_CAPS JOIN3 PNG_CAPS));
static GstStaticPadTemplate t_snk = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS (ARGB_CAPS
GST_VIDEO_CAPS_YUV ("Y800") " ; "
"video/x-raw-gray, "
"bpp = 8, "
"depth = 8, "
"width = " GST_VIDEO_SIZE_RANGE ", "
"height = " GST_VIDEO_SIZE_RANGE ", " "framerate = " GST_VIDEO_FPS_RANGE
PNG_CAPS2));
GST_BOILERPLATE (GstCairoRender, gst_cairo_render, GstElement,
GST_TYPE_ELEMENT);
static void
gst_cairo_render_init (GstCairoRender * c, GstCairoRenderClass * klass)
{
/* The sink */
c->snk = gst_pad_new_from_static_template (&t_snk, "sink");
gst_pad_set_event_function (c->snk, gst_cairo_render_event);
gst_pad_set_chain_function (c->snk, gst_cairo_render_chain);
gst_pad_set_setcaps_function (c->snk, gst_cairo_render_setcaps_sink);
gst_pad_use_fixed_caps (c->snk);
gst_element_add_pad (GST_ELEMENT (c), c->snk);
/* The source */
c->src = gst_pad_new_from_static_template (&t_src, "src");
gst_pad_use_fixed_caps (c->src);
gst_element_add_pad (GST_ELEMENT (c), c->src);
c->width = 0;
c->height = 0;
c->stride = 0;
}
static void
gst_cairo_render_base_init (gpointer g_class)
{
GstElementClass *ec = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_static_metadata (ec, "Cairo encoder",
"Codec/Encoder", "Encodes streams using Cairo",
"Lutz Mueller <lutz@topfrose.de>");
gst_element_class_add_pad_template (ec, gst_static_pad_template_get (&t_snk));
gst_element_class_add_pad_template (ec, gst_static_pad_template_get (&t_src));
}
static void
gst_cairo_render_finalize (GObject * object)
{
GstCairoRender *c = GST_CAIRO_RENDER (object);
if (c->surface) {
cairo_surface_destroy (c->surface);
c->surface = NULL;
}
G_OBJECT_CLASS (parent_class)->finalize (object);
}
static void
gst_cairo_render_class_init (GstCairoRenderClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
gobject_class->finalize = gst_cairo_render_finalize;
GST_DEBUG_CATEGORY_INIT (cairo_render_debug, "cairo_render", 0,
"Cairo encoder");
}