1 /*****************************************************************************
2 * svg.c : Put SVG on the video
3 *****************************************************************************
4 * Copyright (C) 2002, 2003 VideoLAN
5 * $Id: svg.c,v 1.2 2003/07/23 17:26:56 oaubert Exp $
7 * Authors: Olivier Aubert <oaubert@lisi.univ-lyon1.fr>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option ) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
27 #include <stdlib.h> /* malloc( ), free( ) */
30 #include <sys/types.h>
37 #include "vlc_block.h"
38 #include "vlc_filter.h"
40 #include <librsvg-2/librsvg/rsvg.h>
42 typedef struct svg_rendition_t svg_rendition_t;
44 /*****************************************************************************
46 *****************************************************************************/
47 static int Create ( vlc_object_t * );
48 static void Destroy ( vlc_object_t * );
49 static int RenderText( filter_t *p_filter, subpicture_region_t *p_region_out,
50 subpicture_region_t *p_region_in );
53 /*****************************************************************************
55 *****************************************************************************/
57 #define TEMPLATE_TEXT N_( "SVG template file" )
58 #define TEMPLATE_LONGTEXT N_( "Location of a file holding a SVG template for automatic string conversion" )
61 set_capability( "text renderer", 101 );
62 add_shortcut( "svg" );
63 add_string( "svg-template-file", "", NULL, TEMPLATE_TEXT, TEMPLATE_LONGTEXT, VLC_TRUE );
64 set_callbacks( Create, Destroy );
68 Describes a SVG string to be displayed on the video
70 struct svg_rendition_t
75 /** The SVG source associated with this subpicture */
77 /* The rendered SVG, as a GdkPixbuf */
78 GdkPixbuf *p_rendition;
81 static int Render( filter_t *, subpicture_region_t *, svg_rendition_t *, int, int);
82 static byte_t *svg_GetTemplate ();
83 static void svg_set_size( filter_t *p_filter, int width, int height );
84 static void svg_SizeCallback ( int *width, int *height, gpointer data );
85 static void svg_RenderPicture ( filter_t *p_filter,
86 svg_rendition_t *p_svg );
87 static void FreeString( svg_rendition_t * );
89 /*****************************************************************************
90 * filter_sys_t: svg local data
91 *****************************************************************************
92 * This structure is part of the filter thread descriptor.
93 * It describes the svg specific properties of an output thread.
94 *****************************************************************************/
97 /* The SVG template used to convert strings */
99 /* Default size for rendering. Initialized to the output size. */
105 /*****************************************************************************
106 * Create: allocates svg video thread output method
107 *****************************************************************************
108 * This function allocates and initializes a vout method.
109 *****************************************************************************/
110 static int Create( vlc_object_t *p_this )
112 filter_t *p_filter = (filter_t *)p_this;
115 /* Allocate structure */
116 p_sys = malloc( sizeof( filter_sys_t ) );
119 msg_Err( p_filter, "Out of memory" );
123 /* Initialize psz_template */
124 p_sys->psz_template = svg_GetTemplate( p_this );
125 if( !p_sys->psz_template )
127 msg_Err( p_filter, "Out of memory" );
131 p_sys->i_width = p_filter->fmt_out.video.i_width;
132 p_sys->i_height = p_filter->fmt_out.video.i_height;
134 p_filter->pf_render_text = RenderText;
135 p_filter->p_sys = p_sys;
137 /* MUST call this before any RSVG funcs */
143 static byte_t *svg_GetTemplate( vlc_object_t *p_this )
145 filter_t *p_filter = (filter_t *)p_this;
150 psz_filename = config_GetPsz( p_filter, "svg-template-file" );
151 if( !psz_filename || psz_filename[0] == 0 )
153 /* No filename. Use a default value. */
158 /* Read the template */
159 file = fopen( psz_filename, "rt" );
162 msg_Warn( p_this, "SVG template file %s does not exist.", psz_filename );
170 i_ret = lstat( psz_filename, &s );
173 /* Problem accessing file information. Should not
174 happen as we could open it. */
179 msg_Dbg( p_this, "Reading %ld bytes from template %s\n", (long)s.st_size, psz_filename );
181 psz_template = malloc( s.st_size + 42 );
184 msg_Err( p_filter, "Out of memory" );
187 memset( psz_template, 0, s.st_size + 1 );
188 fread( psz_template, s.st_size, 1, file );
195 /* Either there was no file, or there was an error.
196 Use the default value */
197 psz_template = strdup( "<?xml version='1.0' encoding='UTF-8' standalone='no'?> \
198 <svg version='1' preserveAspectRatio='xMinYMin meet' viewBox='0 0 800 600'> \
199 <text x='10' y='560' fill='white' font-size='32' \
200 font-family='sans-serif'>%s</text></svg>" );
206 /*****************************************************************************
207 * Destroy: destroy Clone video thread output method
208 *****************************************************************************
209 * Clean up all data and library connections
210 *****************************************************************************/
211 static void Destroy( vlc_object_t *p_this )
213 filter_t *p_filter = (filter_t *)p_this;
214 filter_sys_t *p_sys = p_filter->p_sys;
216 free( p_sys->psz_template );
220 /*****************************************************************************
221 * Render: render SVG in picture
222 *****************************************************************************/
223 static int Render( filter_t *p_filter, subpicture_region_t *p_region,
224 svg_rendition_t *p_svg, int i_width, int i_height )
227 uint8_t *p_y, *p_u, *p_v, *p_a;
228 int x, y, i_pitch, i_u_pitch;
229 guchar *pixels_in = NULL;
234 subpicture_region_t *p_region_tmp;
236 if ( p_filter->p_sys->i_width != i_width ||
237 p_filter->p_sys->i_height != i_height )
239 svg_set_size( p_filter, i_width, i_height );
240 p_svg->p_rendition = NULL;
243 if( p_svg->p_rendition == NULL ) {
244 svg_RenderPicture( p_filter, p_svg );
245 /* FIXME: should do a check here to ensure that
246 the rendition went OK */
248 i_width = gdk_pixbuf_get_width( p_svg->p_rendition );
249 i_height = gdk_pixbuf_get_height( p_svg->p_rendition );
251 /* Create a new subpicture region */
252 memset( &fmt, 0, sizeof(video_format_t) );
253 fmt.i_chroma = VLC_FOURCC('Y','U','V','A');
254 fmt.i_aspect = VOUT_ASPECT_FACTOR;
255 fmt.i_width = fmt.i_visible_width = i_width;
256 fmt.i_height = fmt.i_visible_height = i_height;
257 fmt.i_x_offset = fmt.i_y_offset = 0;
258 p_region_tmp = spu_CreateRegion( p_filter, &fmt );
261 msg_Err( p_filter, "cannot allocate SPU region" );
264 p_region->fmt = p_region_tmp->fmt;
265 p_region->picture = p_region_tmp->picture;
266 free( p_region_tmp );
268 p_region->i_x = p_region->i_y = 0;
269 p_y = p_region->picture.Y_PIXELS;
270 p_u = p_region->picture.U_PIXELS;
271 p_v = p_region->picture.V_PIXELS;
272 p_a = p_region->picture.A_PIXELS;
274 i_pitch = p_region->picture.Y_PITCH;
275 i_u_pitch = p_region->picture.U_PITCH;
277 /* Initialize the region pixels (only the alpha will be changed later) */
278 memset( p_y, 0x00, i_pitch * p_region->fmt.i_height );
279 memset( p_u, 0x80, i_u_pitch * p_region->fmt.i_height );
280 memset( p_v, 0x80, i_u_pitch * p_region->fmt.i_height );
282 p_pic = &(p_region->picture);
286 /* This rendering code is in no way optimized. If someone has some time to
287 make it work faster or better, please do.
291 p_pixbuf->get_rowstride() is the number of bytes in a line.
292 p_pixbuf->get_height() is the number of lines.
294 The number of bytes of p_pixbuf->p_pixels is get_rowstride * get_height
297 alpha = pixels [ n_channels * ( y*rowstride + x ) + 3 ];
299 red = pixels [ n_channels * ( y*rowstride ) + x ) ];
300 green = pixels [ n_channels * ( y*rowstride ) + x ) + 1 ];
301 blue = pixels [ n_channels * ( y*rowstride ) + x ) + 2 ];
304 pixels_in = gdk_pixbuf_get_pixels( p_svg->p_rendition );
305 rowstride_in = gdk_pixbuf_get_rowstride( p_svg->p_rendition );
306 channels_in = gdk_pixbuf_get_n_channels( p_svg->p_rendition );
307 alpha = gdk_pixbuf_get_has_alpha( p_svg->p_rendition );
310 This crashes the plugin (if !alpha). As there is always an alpha value,
311 it does not matter for the moment :
314 memset( p_a, 0xFF, i_pitch * p_region->fmt.i_height );
317 #define INDEX_IN( x, y ) ( y * rowstride_in + x * channels_in )
318 #define INDEX_OUT( x, y ) ( y * i_pitch + x * p_pic->p[Y_PLANE].i_pixel_pitch )
320 for( y = 0; y < i_height; y++ )
322 for( x = 0; x < i_width; x++ )
327 p_in = &pixels_in[INDEX_IN( x, y )];
329 #define R( pixel ) *pixel
330 #define G( pixel ) *( pixel+1 )
331 #define B( pixel ) *( pixel+2 )
332 #define ALPHA( pixel ) *( pixel+3 )
334 /* From http://www.geocrawler.com/archives/3/8263/2001/6/0/6020594/ :
335 Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
336 U = -0.1687 * r - 0.3313 * g + 0.5 * b + 128
337 V = 0.5 * r - 0.4187 * g - 0.0813 * b + 128
340 i_out = INDEX_OUT( x, y );
342 p_pic->Y_PIXELS[i_out] = .299 * R( p_in ) + .587 * G( p_in ) + .114 * B( p_in );
344 p_pic->U_PIXELS[i_out] = -.1687 * R( p_in ) - .3313 * G( p_in ) + .5 * B( p_in ) + 128;
345 p_pic->V_PIXELS[i_out] = .5 * R( p_in ) - .4187 * G( p_in ) - .0813 * B( p_in ) + 128;
347 p_pic->A_PIXELS[i_out] = ALPHA( p_in );
355 static void svg_set_size( filter_t *p_filter, int width, int height )
357 p_filter->p_sys->i_width = width;
358 p_filter->p_sys->i_height = height;
361 static void svg_SizeCallback( int *width, int *height, gpointer data )
363 filter_t *p_filter = data;
365 *width = p_filter->p_sys->i_width;
366 *height = p_filter->p_sys->i_height;
370 static void svg_RenderPicture( filter_t *p_filter,
371 svg_rendition_t *p_svg )
373 /* Render the SVG string p_string->psz_text into a new picture_t
374 p_string->p_rendition with dimensions ( ->i_width, ->i_height ) */
375 RsvgHandle *p_handle;
376 GError *error = NULL;
378 p_handle = rsvg_handle_new();
380 rsvg_handle_set_size_callback( p_handle, svg_SizeCallback, p_filter, NULL );
382 rsvg_handle_write( p_handle,
383 p_svg->psz_text, strlen( p_svg->psz_text ) + 1,
387 msg_Err( p_filter, "Error in handle_write: %s\n", error->message );
390 rsvg_handle_close( p_handle, &error );
392 p_svg->p_rendition = rsvg_handle_get_pixbuf( p_handle );
393 rsvg_handle_free( p_handle );
397 static int RenderText( filter_t *p_filter, subpicture_region_t *p_region_out,
398 subpicture_region_t *p_region_in )
400 filter_sys_t *p_sys = p_filter->p_sys;
401 svg_rendition_t *p_svg = NULL;
405 if( !p_region_in || !p_region_out ) return VLC_EGENERIC;
406 psz_string = p_region_in->psz_text;
407 if( !psz_string || !*psz_string ) return VLC_EGENERIC;
409 p_svg = ( svg_rendition_t * )malloc( sizeof( svg_rendition_t ) );
412 msg_Err( p_filter, "Out of memory" );
416 p_region_out->i_x = p_region_in->i_x;
417 p_region_out->i_y = p_region_in->i_y;
419 /* Check if the data is SVG or pure text. In the latter case,
420 convert the text to SVG. FIXME: find a better test */
421 if( strstr( psz_string, "<svg" ))
423 /* Data is SVG: duplicate */
424 p_svg->psz_text = strdup( psz_string );
425 if( !p_svg->psz_text )
427 msg_Err( p_filter, "Out of memory" );
434 /* Data is text. Convert to SVG */
436 byte_t* psz_template = p_sys->psz_template;
437 length = strlen( psz_string ) + strlen( psz_template ) + 42;
438 p_svg->psz_text = malloc( length + 1 );
439 if( !p_svg->psz_text )
441 msg_Err( p_filter, "Out of memory" );
445 memset( p_svg->psz_text, 0, length + 1 );
446 snprintf( p_svg->psz_text, length, psz_template, psz_string );
448 p_svg->i_width = p_sys->i_width;
449 p_svg->i_height = p_sys->i_height;
450 p_svg->i_chroma = VLC_FOURCC('Y','U','V','A');
453 The input data is stored in the p_string structure,
454 and the function updates the p_rendition attribute. */
455 svg_RenderPicture( p_filter, p_svg );
457 Render( p_filter, p_region_out, p_svg, p_svg->i_width, p_svg->i_height );
463 static void FreeString( svg_rendition_t *p_svg )
465 free( p_svg->psz_text );
466 free( p_svg->p_rendition );