2 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
5 * Copyright (C) 2000 Donald A. Graft
7 * This library is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 * Library General Public License for more details.
12 * You should have received a copy of the GNU Library General Public
13 * License along with this library; if not, write to the
14 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
15 * Boston, MA 02111-1307, USA.
21 #include "gstpngenc.h"
23 #define MAX_HEIGHT 4096
26 GstElementDetails gst_pngenc_details = {
28 "Filter/Video/Effect",
30 "Encode a video frame to a .png image"
32 "Jeremy SIMON <jsimon13@yahoo.fr>",
33 "(C) 2000 Donald Graft",
37 /* Filter signals and args */
49 static void gst_pngenc_class_init (GstPngEncClass *klass);
50 static void gst_pngenc_init (GstPngEnc *pngenc);
52 static void gst_pngenc_chain (GstPad *pad, GstBuffer *buf);
54 static GstElementClass *parent_class = NULL;
57 static void user_error_fn (png_structp png_ptr, png_const_charp error_msg)
59 g_warning("%s", error_msg);
62 static void user_warning_fn (png_structp png_ptr, png_const_charp warning_msg)
64 g_warning("%s", warning_msg);
68 GType gst_pngenc_get_type (void)
70 static GType pngenc_type = 0;
73 static const GTypeInfo pngenc_info = {
74 sizeof (GstPngEncClass), NULL,
76 (GClassInitFunc) gst_pngenc_class_init,
81 (GInstanceInitFunc) gst_pngenc_init,
84 pngenc_type = g_type_register_static (GST_TYPE_ELEMENT, "GstPngEnc",
91 gst_pngenc_class_init (GstPngEncClass *klass)
93 GObjectClass *gobject_class;
94 GstElementClass *gstelement_class;
96 gobject_class = (GObjectClass *) klass;
97 gstelement_class = (GstElementClass *) klass;
99 parent_class = g_type_class_ref (GST_TYPE_ELEMENT);
103 static GstPadLinkReturn
104 gst_pngenc_sinklink (GstPad *pad, GstCaps *caps)
108 pngenc = GST_PNGENC (gst_pad_get_parent (pad));
110 if (!GST_CAPS_IS_FIXED (caps))
111 return GST_PAD_LINK_DELAYED;
113 gst_caps_get_int (caps, "width", &pngenc->width);
114 gst_caps_get_int (caps, "height", &pngenc->height);
115 gst_caps_get_int (caps, "bpp", &pngenc->bpp);
117 return gst_pad_try_set_caps (pngenc->srcpad, caps);
121 gst_pngenc_init (GstPngEnc * pngenc)
123 pngenc->sinkpad = gst_pad_new_from_template (pngenc_sink_template, "sink");
124 gst_element_add_pad (GST_ELEMENT (pngenc), pngenc->sinkpad);
126 pngenc->srcpad = gst_pad_new ("src", GST_PAD_SRC);
127 gst_element_add_pad (GST_ELEMENT (pngenc), pngenc->srcpad);
129 gst_pad_set_chain_function (pngenc->sinkpad, gst_pngenc_chain);
130 gst_pad_set_link_function (pngenc->sinkpad, gst_pngenc_sinklink);
132 pngenc->png_struct_ptr = NULL;
133 pngenc->png_info_ptr = NULL;
137 void user_flush_data (png_structp png_ptr)
141 pngenc = (GstPngEnc *) png_get_io_ptr (png_ptr);
143 gst_pad_push (pngenc->srcpad, GST_BUFFER (gst_event_new (GST_EVENT_FLUSH)));
147 void user_write_data (png_structp png_ptr, png_bytep data, png_uint_32 length)
152 pngenc = (GstPngEnc *) png_get_io_ptr (png_ptr);
154 buffer = gst_buffer_new();
155 GST_BUFFER_DATA (buffer) = g_memdup (data, length);
156 GST_BUFFER_SIZE (buffer) = length;
158 if (pngenc->buffer_out)
160 pngenc->buffer_out = gst_buffer_merge (pngenc->buffer_out, buffer);
161 gst_buffer_unref (buffer);
164 pngenc->buffer_out = buffer;
168 gst_pngenc_chain (GstPad *pad, GstBuffer *buf)
172 png_byte *row_pointers[MAX_HEIGHT];
175 pngenc = GST_PNGENC (gst_pad_get_parent (pad));
177 pngenc->buffer_out = NULL;
178 if (!GST_PAD_IS_USABLE (pngenc->srcpad))
180 gst_buffer_unref (buf);
184 /* initialize png struct stuff */
185 pngenc->png_struct_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING,
186 (png_voidp) NULL, user_error_fn, user_warning_fn);
187 /* FIXME: better error handling */
188 if (pngenc->png_struct_ptr == NULL)
189 g_warning ("Failed to initialize png structure");
191 pngenc->png_info_ptr = png_create_info_struct (pngenc->png_struct_ptr);
192 if (!pngenc->png_info_ptr)
194 png_destroy_read_struct (&(pngenc->png_struct_ptr), (png_infopp) NULL,
198 /* non-0 return is from a longjmp inside of libpng */
199 if (setjmp (pngenc->png_struct_ptr->jmpbuf) != 0)
201 GST_DEBUG (GST_CAT_PLUGIN_INFO, "returning from longjmp");
202 png_destroy_write_struct (&pngenc->png_struct_ptr, &pngenc->png_info_ptr);
206 png_set_filter (pngenc->png_struct_ptr, 0,
207 PNG_FILTER_NONE | PNG_FILTER_VALUE_NONE);
208 png_set_compression_level (pngenc->png_struct_ptr, 9);
211 pngenc->png_struct_ptr,
212 pngenc->png_info_ptr,
218 PNG_COMPRESSION_TYPE_DEFAULT,
219 PNG_FILTER_TYPE_DEFAULT
222 png_set_write_fn (pngenc->png_struct_ptr, pngenc,
223 (png_rw_ptr) user_write_data, user_flush_data);
225 for (row_index = 0; row_index < pngenc->height; row_index++)
226 row_pointers[row_index] = GST_BUFFER_DATA (buf) +
227 (pngenc->width * row_index * pngenc->bpp / 8);
229 png_write_info (pngenc->png_struct_ptr, pngenc->png_info_ptr);
230 png_write_image (pngenc->png_struct_ptr, row_pointers);
231 png_write_end (pngenc->png_struct_ptr, NULL);
233 user_flush_data (pngenc->png_struct_ptr);
235 png_destroy_info_struct (pngenc->png_struct_ptr, &pngenc->png_info_ptr);
236 png_destroy_write_struct (&pngenc->png_struct_ptr, (png_infopp) NULL);
238 gst_pad_push (pngenc->srcpad, pngenc->buffer_out);
240 /* send EOS event, since a frame has been pushed out */
241 event = gst_event_new (GST_EVENT_EOS);
242 gst_pad_push (pngenc->srcpad, GST_BUFFER (event));
244 gst_buffer_unref (buf);