modules/codec/svg.c

   1 /*****************************************************************************
   2  * svg.c: svg decoder module making use of librsvg2.
   3  *****************************************************************************
   4  * Copyright (C) 2014 VLC authors and VideoLAN
   5  *
   6  * Authors: Adam Leggett <adamvleggett@gmail.com>
   7  *          Jean-Paul Saman <jpsaman@videolan.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU Lesser General Public License as published by
  11  * the Free Software Foundation; either version 2.1 of the License, or
  12  * (at your option) any later version.
  13  *
  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 Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public License
  20  * along with this program; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_codec.h>
  34
  35 #include <glib.h>
  36 #include <glib/gstdio.h>
  37 #include <glib-object.h>                                  /* g_object_unref( ) */
  38
  39 #include <librsvg/rsvg.h>
  40 #include <cairo/cairo.h>
  41
  42 /*****************************************************************************
  43  * Local prototypes
  44  *****************************************************************************/
  45 static int  OpenDecoder   ( vlc_object_t * );
  46 static void CloseDecoder  ( vlc_object_t * );
  47
  48 static int DecodeBlock  ( decoder_t *, block_t * );
  49
  50 #define TEXT_WIDTH       N_("Image width")
  51 #define LONG_TEXT_WIDTH  N_("Specify the width to decode the image too")
  52 #define TEXT_HEIGHT      N_("Image height")
  53 #define LONG_TEXT_HEIGHT N_("Specify the height to decode the image too")
  54 #define TEXT_SCALE       N_("Scale factor")
  55 #define LONG_TEXT_SCALE  N_("Scale factor to apply to image")
  56
  57 /*****************************************************************************
  58  * Module descriptor
  59  *****************************************************************************/
  60 vlc_module_begin ()
  61     set_category( CAT_INPUT )
  62     set_subcategory( SUBCAT_INPUT_VCODEC )
  63     set_description( N_("SVG video decoder") )
  64     set_capability( "decoder", 100 )
  65     set_callbacks( OpenDecoder, CloseDecoder )
  66     add_shortcut( "svg" )
  67
  68     /* svg options */
  69     add_integer_with_range( "svg-width", -1, 1, 65535,
  70                             TEXT_WIDTH, LONG_TEXT_WIDTH, false )
  71         change_safe()
  72     add_integer_with_range( "svg-height", -1, 1, 65535,
  73                             TEXT_HEIGHT, LONG_TEXT_HEIGHT, false )
  74         change_safe()
  75
  76     add_float( "svg-scale", -1.0, TEXT_SCALE, LONG_TEXT_SCALE, false )
  77 vlc_module_end ()
  78
  79 struct decoder_sys_t
  80 {
  81     int32_t i_width;
  82     int32_t i_height;
  83     double  f_scale;
  84 };
  85
  86 /*****************************************************************************
  87  * OpenDecoder: probe the decoder and return score
  88  *****************************************************************************/
  89 static int OpenDecoder( vlc_object_t *p_this )
  90 {
  91     decoder_t *p_dec = (decoder_t*)p_this;
  92
  93     if( p_dec->fmt_in.i_codec != VLC_CODEC_SVG )
  94         return VLC_EGENERIC;
  95
  96     decoder_sys_t *p_sys = malloc( sizeof(decoder_sys_t) );
  97     if (!p_sys)
  98         return VLC_ENOMEM;
  99     p_dec->p_sys = p_sys;
 100
 101     p_sys->i_width = var_InheritInteger( p_this, "svg-width" );
 102     p_sys->i_height = var_InheritInteger( p_this, "svg-height" );
 103     p_sys->f_scale = var_InheritFloat( p_this, "svg-scale" );
 104
 105     /* Initialize library */
 106 #if (GLIB_MAJOR_VERSION < 2 || GLIB_MINOR_VERSION < 36)
 107     g_type_init();
 108 #endif
 109
 110     /* Set output properties */
 111     p_dec->fmt_out.i_cat = VIDEO_ES;
 112     p_dec->fmt_out.i_codec = VLC_CODEC_BGRA;
 113
 114     /* Set callbacks */
 115     p_dec->pf_decode = DecodeBlock;
 116
 117     return VLC_SUCCESS;
 118 }
 119
 120 /****************************************************************************
 121  * DecodeBlock: the whole thing
 122  ****************************************************************************
 123  * This function must be fed with a complete image.
 124  ****************************************************************************/
 125 static int DecodeBlock( decoder_t *p_dec, block_t *p_block )
 126 {
 127     decoder_sys_t *p_sys  = (decoder_sys_t *) p_dec->p_sys;
 128     picture_t *p_pic = NULL;
 129     int32_t i_width, i_height;
 130
 131     RsvgHandle *rsvg = NULL;
 132     cairo_surface_t *surface = NULL;
 133     cairo_t *cr = NULL;
 134
 135     if( p_block == NULL ) /* No Drain */
 136         return VLCDEC_SUCCESS;
 137
 138     if( p_block->i_flags & BLOCK_FLAG_CORRUPTED)
 139     {
 140         block_Release( p_block );
 141         return VLCDEC_SUCCESS;
 142     }
 143
 144     rsvg = rsvg_handle_new_from_data( p_block->p_buffer, p_block->i_buffer, NULL );
 145     if( !rsvg )
 146         goto done;
 147
 148     RsvgDimensionData dim;
 149     rsvg_handle_get_dimensions( rsvg, &dim );
 150
 151     if( p_sys->f_scale > 0.0 )
 152     {
 153         i_width  = (int32_t)(p_sys->f_scale * dim.width);
 154         i_height = (int32_t)(p_sys->f_scale * dim.height);
 155     }
 156     else
 157     {
 158         /* Keep aspect */
 159         if( p_sys->i_width < 0 && p_sys->i_height > 0 )
 160         {
 161             i_width  = dim.width * p_sys->i_height / dim.height;
 162             i_height = p_sys->i_height;
 163         }
 164         else if( p_sys->i_width > 0 && p_sys->i_height < 0 )
 165         {
 166             i_width  = p_sys->i_width;
 167             i_height = dim.height * p_sys->i_width / dim.height;
 168         }
 169         else if( p_sys->i_width > 0 && p_sys->i_height > 0 )
 170         {
 171             i_width  = dim.width * p_sys->i_height / dim.height;
 172             i_height = p_sys->i_height;
 173         }
 174         else
 175         {
 176             i_width  = dim.width;
 177             i_height = dim.height;
 178         }
 179     }
 180
 181     p_dec->fmt_out.i_codec =
 182     p_dec->fmt_out.video.i_chroma = VLC_CODEC_BGRA;
 183     p_dec->fmt_out.video.i_width  = i_width;
 184     p_dec->fmt_out.video.i_height = i_height;
 185     p_dec->fmt_out.video.i_visible_width  = i_width;
 186     p_dec->fmt_out.video.i_visible_height = i_height;
 187     p_dec->fmt_out.video.i_sar_num = 1;
 188     p_dec->fmt_out.video.i_sar_den = 1;
 189     p_dec->fmt_out.video.i_rmask = 0x80800000; /* Since librsvg v1.0 */
 190     p_dec->fmt_out.video.i_gmask = 0x0000ff00;
 191     p_dec->fmt_out.video.i_bmask = 0x000000ff;
 192     video_format_FixRgb(&p_dec->fmt_out.video);
 193
 194     /* Get a new picture */
 195     if( decoder_UpdateVideoFormat( p_dec ) )
 196         goto done;
 197     p_pic = decoder_NewPicture( p_dec );
 198     if( !p_pic )
 199         goto done;
 200
 201     /* NOTE: Do not use the stride calculation from cairo, because it is wrong:
 202      * stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, dim.width);
 203      * Use the stride from VLC its picture_t::p[0].i_pitch, which is correct.
 204      */
 205     memset(p_pic->p[0].p_pixels, 0, p_pic->p[0].i_pitch * p_pic->p[0].i_lines);
 206     surface = cairo_image_surface_create_for_data( p_pic->p->p_pixels,
 207                                                    CAIRO_FORMAT_ARGB32,
 208                                                    i_width, i_height,
 209                                                    p_pic->p[0].i_pitch );
 210     if( !surface )
 211     {
 212         picture_Release( p_pic );
 213         p_pic = NULL;
 214         goto done;
 215     }
 216
 217     /* Decode picture */
 218     cr = cairo_create( surface );
 219     if( !cr )
 220     {
 221         picture_Release( p_pic );
 222         p_pic = NULL;
 223         goto done;
 224     }
 225
 226     if ( i_width != dim.width || i_height != dim.height )
 227     {
 228         double sw, sh;
 229         if ( p_sys->f_scale > 0.0 && !(p_sys->i_width > 0 || p_sys->i_height > 0) )
 230             sw = sh = p_sys->f_scale;
 231         else
 232         {
 233             double aspect = (double) (dim.width * p_dec->fmt_out.video.i_sar_num) /
 234                     (dim.height * p_dec->fmt_out.video.i_sar_den);
 235             sw = aspect * i_width / dim.width;
 236             sh = aspect * i_height / dim.height;
 237         }
 238         cairo_scale(cr, sw, sh);
 239     }
 240
 241     if( !rsvg_handle_render_cairo( rsvg, cr ) )
 242     {
 243         picture_Release( p_pic );
 244         p_pic = NULL;
 245         goto done;
 246     }
 247
 248     p_pic->date = p_block->i_pts > VLC_TS_INVALID ? p_block->i_pts : p_block->i_dts;
 249
 250 done:
 251     if( rsvg )
 252         g_object_unref( G_OBJECT( rsvg ) );
 253     if( cr )
 254         cairo_destroy( cr );
 255     if( surface )
 256         cairo_surface_destroy( surface );
 257
 258     block_Release( p_block );
 259     if( p_pic != NULL )
 260         decoder_QueueVideo( p_dec, p_pic );
 261     return VLCDEC_SUCCESS;
 262 }
 263
 264 /*****************************************************************************
 265  * CloseDecoder: png decoder destruction
 266  *****************************************************************************/
 267 static void CloseDecoder( vlc_object_t *p_this )
 268 {
 269     VLC_UNUSED( p_this );
 270 #if (GLIB_MAJOR_VERSION < 2 || GLIB_MINOR_VERSION < 36)
 271     rsvg_term();
 272 #endif
 273 }