1 /*****************************************************************************
2 * svg.c : Put SVG on the video
3 *****************************************************************************
4 * Copyright (C) 2002, 2003 the VideoLAN team
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_category( CAT_INPUT);
62 set_category( SUBCAT_INPUT_SCODEC );
63 set_capability( "text renderer", 101 );
64 add_shortcut( "svg" );
65 add_string( "svg-template-file", "", NULL, TEMPLATE_TEXT, TEMPLATE_LONGTEXT, VLC_TRUE );
66 set_callbacks( Create, Destroy );
70 Describes a SVG string to be displayed on the video
72 struct svg_rendition_t
77 /** The SVG source associated with this subpicture */
79 /* The rendered SVG, as a GdkPixbuf */
80 GdkPixbuf *p_rendition;
83 static int Render( filter_t *, subpicture_region_t *, svg_rendition_t *, int, int);
84 static byte_t *svg_GetTemplate ();
85 static void svg_set_size( filter_t *p_filter, int width, int height );
86 static void svg_SizeCallback ( int *width, int *height, gpointer data );
87 static void svg_RenderPicture ( filter_t *p_filter,
88 svg_rendition_t *p_svg );
89 static void FreeString( svg_rendition_t * );
91 /*****************************************************************************
92 * filter_sys_t: svg local data
93 *****************************************************************************
94 * This structure is part of the filter thread descriptor.
95 * It describes the svg specific properties of an output thread.
96 *****************************************************************************/
99 /* The SVG template used to convert strings */
100 byte_t *psz_template;
101 /* Default size for rendering. Initialized to the output size. */
107 /*****************************************************************************
108 * Create: allocates svg video thread output method
109 *****************************************************************************
110 * This function allocates and initializes a vout method.
111 *****************************************************************************/
112 static int Create( vlc_object_t *p_this )
114 filter_t *p_filter = (filter_t *)p_this;
117 /* Allocate structure */
118 p_sys = malloc( sizeof( filter_sys_t ) );
121 msg_Err( p_filter, "Out of memory" );
125 /* Initialize psz_template */
126 p_sys->psz_template = svg_GetTemplate( p_this );
127 if( !p_sys->psz_template )
129 msg_Err( p_filter, "Out of memory" );
133 p_sys->i_width = p_filter->fmt_out.video.i_width;
134 p_sys->i_height = p_filter->fmt_out.video.i_height;
136 p_filter->pf_render_text = RenderText;
137 p_filter->p_sys = p_sys;
139 /* MUST call this before any RSVG funcs */
145 static byte_t *svg_GetTemplate( vlc_object_t *p_this )
147 filter_t *p_filter = (filter_t *)p_this;
152 psz_filename = config_GetPsz( p_filter, "svg-template-file" );
153 if( !psz_filename || psz_filename[0] == 0 )
155 /* No filename. Use a default value. */
160 /* Read the template */
161 file = fopen( psz_filename, "rt" );
164 msg_Warn( p_this, "SVG template file %s does not exist.", psz_filename );
172 i_ret = lstat( psz_filename, &s );
175 /* Problem accessing file information. Should not
176 happen as we could open it. */
181 msg_Dbg( p_this, "Reading %ld bytes from template %s\n", (long)s.st_size, psz_filename );
183 psz_template = malloc( s.st_size + 42 );
186 msg_Err( p_filter, "Out of memory" );
189 memset( psz_template, 0, s.st_size + 1 );
190 fread( psz_template, s.st_size, 1, file );
197 /* Either there was no file, or there was an error.
198 Use the default value */
199 psz_template = strdup( "<?xml version='1.0' encoding='UTF-8' standalone='no'?> \
200 <svg version='1' preserveAspectRatio='xMinYMin meet' viewBox='0 0 800 600'> \
201 <text x='10' y='560' fill='white' font-size='32' \
202 font-family='sans-serif'>%s</text></svg>" );
208 /*****************************************************************************
209 * Destroy: destroy Clone video thread output method
210 *****************************************************************************
211 * Clean up all data and library connections
212 *****************************************************************************/
213 static void Destroy( vlc_object_t *p_this )
215 filter_t *p_filter = (filter_t *)p_this;
216 filter_sys_t *p_sys = p_filter->p_sys;
218 free( p_sys->psz_template );
222 /*****************************************************************************
223 * Render: render SVG in picture
224 *****************************************************************************/
225 static int Render( filter_t *p_filter, subpicture_region_t *p_region,
226 svg_rendition_t *p_svg, int i_width, int i_height )
229 uint8_t *p_y, *p_u, *p_v, *p_a;
230 int x, y, i_pitch, i_u_pitch;
231 guchar *pixels_in = NULL;
236 subpicture_region_t *p_region_tmp;
238 if ( p_filter->p_sys->i_width != i_width ||
239 p_filter->p_sys->i_height != i_height )
241 svg_set_size( p_filter, i_width, i_height );
242 p_svg->p_rendition = NULL;
245 if( p_svg->p_rendition == NULL ) {
246 svg_RenderPicture( p_filter, p_svg );
247 /* FIXME: should do a check here to ensure that
248 the rendition went OK */
250 i_width = gdk_pixbuf_get_width( p_svg->p_rendition );
251 i_height = gdk_pixbuf_get_height( p_svg->p_rendition );
253 /* Create a new subpicture region */
254 memset( &fmt, 0, sizeof(video_format_t) );
255 fmt.i_chroma = VLC_FOURCC('Y','U','V','A');
256 fmt.i_aspect = VOUT_ASPECT_FACTOR;
257 fmt.i_width = fmt.i_visible_width = i_width;
258 fmt.i_height = fmt.i_visible_height = i_height;
259 fmt.i_x_offset = fmt.i_y_offset = 0;
260 p_region_tmp = spu_CreateRegion( p_filter, &fmt );
263 msg_Err( p_filter, "cannot allocate SPU region" );
266 p_region->fmt = p_region_tmp->fmt;
267 p_region->picture = p_region_tmp->picture;
268 free( p_region_tmp );
270 p_region->i_x = p_region->i_y = 0;
271 p_y = p_region->picture.Y_PIXELS;
272 p_u = p_region->picture.U_PIXELS;
273 p_v = p_region->picture.V_PIXELS;
274 p_a = p_region->picture.A_PIXELS;
276 i_pitch = p_region->picture.Y_PITCH;
277 i_u_pitch = p_region->picture.U_PITCH;
279 /* Initialize the region pixels (only the alpha will be changed later) */
280 memset( p_y, 0x00, i_pitch * p_region->fmt.i_height );
281 memset( p_u, 0x80, i_u_pitch * p_region->fmt.i_height );
282 memset( p_v, 0x80, i_u_pitch * p_region->fmt.i_height );
284 p_pic = &(p_region->picture);
288 /* This rendering code is in no way optimized. If someone has some time to
289 make it work faster or better, please do.
293 p_pixbuf->get_rowstride() is the number of bytes in a line.
294 p_pixbuf->get_height() is the number of lines.
296 The number of bytes of p_pixbuf->p_pixels is get_rowstride * get_height
299 alpha = pixels [ n_channels * ( y*rowstride + x ) + 3 ];
301 red = pixels [ n_channels * ( y*rowstride ) + x ) ];
302 green = pixels [ n_channels * ( y*rowstride ) + x ) + 1 ];
303 blue = pixels [ n_channels * ( y*rowstride ) + x ) + 2 ];
306 pixels_in = gdk_pixbuf_get_pixels( p_svg->p_rendition );
307 rowstride_in = gdk_pixbuf_get_rowstride( p_svg->p_rendition );
308 channels_in = gdk_pixbuf_get_n_channels( p_svg->p_rendition );
309 alpha = gdk_pixbuf_get_has_alpha( p_svg->p_rendition );
312 This crashes the plugin (if !alpha). As there is always an alpha value,
313 it does not matter for the moment :
316 memset( p_a, 0xFF, i_pitch * p_region->fmt.i_height );
319 #define INDEX_IN( x, y ) ( y * rowstride_in + x * channels_in )
320 #define INDEX_OUT( x, y ) ( y * i_pitch + x * p_pic->p[Y_PLANE].i_pixel_pitch )
322 for( y = 0; y < i_height; y++ )
324 for( x = 0; x < i_width; x++ )
329 p_in = &pixels_in[INDEX_IN( x, y )];
331 #define R( pixel ) *pixel
332 #define G( pixel ) *( pixel+1 )
333 #define B( pixel ) *( pixel+2 )
334 #define ALPHA( pixel ) *( pixel+3 )
336 /* From http://www.geocrawler.com/archives/3/8263/2001/6/0/6020594/ :
337 Y = 0.29900 * R + 0.58700 * G + 0.11400 * B
338 U = -0.1687 * r - 0.3313 * g + 0.5 * b + 128
339 V = 0.5 * r - 0.4187 * g - 0.0813 * b + 128
342 i_out = INDEX_OUT( x, y );
344 p_pic->Y_PIXELS[i_out] = .299 * R( p_in ) + .587 * G( p_in ) + .114 * B( p_in );
346 p_pic->U_PIXELS[i_out] = -.1687 * R( p_in ) - .3313 * G( p_in ) + .5 * B( p_in ) + 128;
347 p_pic->V_PIXELS[i_out] = .5 * R( p_in ) - .4187 * G( p_in ) - .0813 * B( p_in ) + 128;
349 p_pic->A_PIXELS[i_out] = ALPHA( p_in );
357 static void svg_set_size( filter_t *p_filter, int width, int height )
359 p_filter->p_sys->i_width = width;
360 p_filter->p_sys->i_height = height;
363 static void svg_SizeCallback( int *width, int *height, gpointer data )
365 filter_t *p_filter = data;
367 *width = p_filter->p_sys->i_width;
368 *height = p_filter->p_sys->i_height;
372 static void svg_RenderPicture( filter_t *p_filter,
373 svg_rendition_t *p_svg )
375 /* Render the SVG string p_string->psz_text into a new picture_t
376 p_string->p_rendition with dimensions ( ->i_width, ->i_height ) */
377 RsvgHandle *p_handle;
378 GError *error = NULL;
380 p_handle = rsvg_handle_new();
382 rsvg_handle_set_size_callback( p_handle, svg_SizeCallback, p_filter, NULL );
384 rsvg_handle_write( p_handle,
385 p_svg->psz_text, strlen( p_svg->psz_text ) + 1,
389 msg_Err( p_filter, "Error in handle_write: %s\n", error->message );
392 rsvg_handle_close( p_handle, &error );
394 p_svg->p_rendition = rsvg_handle_get_pixbuf( p_handle );
395 rsvg_handle_free( p_handle );
399 static int RenderText( filter_t *p_filter, subpicture_region_t *p_region_out,
400 subpicture_region_t *p_region_in )
402 filter_sys_t *p_sys = p_filter->p_sys;
403 svg_rendition_t *p_svg = NULL;
407 if( !p_region_in || !p_region_out ) return VLC_EGENERIC;
408 psz_string = p_region_in->psz_text;
409 if( !psz_string || !*psz_string ) return VLC_EGENERIC;
411 p_svg = ( svg_rendition_t * )malloc( sizeof( svg_rendition_t ) );
414 msg_Err( p_filter, "Out of memory" );
418 p_region_out->i_x = p_region_in->i_x;
419 p_region_out->i_y = p_region_in->i_y;
421 /* Check if the data is SVG or pure text. In the latter case,
422 convert the text to SVG. FIXME: find a better test */
423 if( strstr( psz_string, "<svg" ))
425 /* Data is SVG: duplicate */
426 p_svg->psz_text = strdup( psz_string );
427 if( !p_svg->psz_text )
429 msg_Err( p_filter, "Out of memory" );
436 /* Data is text. Convert to SVG */
438 byte_t* psz_template = p_sys->psz_template;
439 length = strlen( psz_string ) + strlen( psz_template ) + 42;
440 p_svg->psz_text = malloc( length + 1 );
441 if( !p_svg->psz_text )
443 msg_Err( p_filter, "Out of memory" );
447 memset( p_svg->psz_text, 0, length + 1 );
448 snprintf( p_svg->psz_text, length, psz_template, psz_string );
450 p_svg->i_width = p_sys->i_width;
451 p_svg->i_height = p_sys->i_height;
452 p_svg->i_chroma = VLC_FOURCC('Y','U','V','A');
455 The input data is stored in the p_string structure,
456 and the function updates the p_rendition attribute. */
457 svg_RenderPicture( p_filter, p_svg );
459 Render( p_filter, p_region_out, p_svg, p_svg->i_width, p_svg->i_height );
465 static void FreeString( svg_rendition_t *p_svg )
467 free( p_svg->psz_text );
468 free( p_svg->p_rendition );