1 /*
2 * Librsvg rasterization wrapper
3 * Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #include "avcodec.h"
23 #include "codec_internal.h"
24 #include "internal.h"
25 #include "libavutil/opt.h"
26 #include "librsvg-2.0/librsvg/rsvg.h"
27
28 typedef struct LibRSVGContext {
29 AVClass *class;
30
31 int width;
32 int height;
33 int keep_ar;
34 } LibRSVGContext;
35
librsvg_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame,AVPacket * pkt)36 static int librsvg_decode_frame(AVCodecContext *avctx, AVFrame *frame,
37 int *got_frame, AVPacket *pkt)
38 {
39 int ret;
40 LibRSVGContext *s = avctx->priv_data;
41
42 RsvgHandle *handle;
43 RsvgDimensionData unscaled_dimensions, dimensions;
44 cairo_surface_t *image;
45 cairo_t *crender = NULL;
46 GError *error = NULL;
47
48 *got_frame = 0;
49
50 handle = rsvg_handle_new_from_data(pkt->data, pkt->size, &error);
51 if (error) {
52 av_log(avctx, AV_LOG_ERROR, "Error parsing svg!\n");
53 g_error_free(error);
54 return AVERROR_INVALIDDATA;
55 }
56
57 rsvg_handle_get_dimensions(handle, &dimensions);
58 rsvg_handle_get_dimensions(handle, &unscaled_dimensions);
59 dimensions.width = s->width ? s->width : dimensions.width;
60 dimensions.height = s->height ? s->height : dimensions.height;
61 if (s->keep_ar && (s->width || s->height)) {
62 double default_ar = unscaled_dimensions.width/(double)unscaled_dimensions.height;
63 if (!s->width)
64 dimensions.width = lrintf(dimensions.height * default_ar);
65 else
66 dimensions.height = lrintf(dimensions.width / default_ar);
67 }
68
69 if ((ret = ff_set_dimensions(avctx, dimensions.width, dimensions.height)))
70 return ret;
71 avctx->pix_fmt = AV_PIX_FMT_RGB32;
72
73 if ((ret = ff_get_buffer(avctx, frame, 0)))
74 return ret;
75 frame->pict_type = AV_PICTURE_TYPE_I;
76 frame->key_frame = 1;
77
78 image = cairo_image_surface_create_for_data(frame->data[0], CAIRO_FORMAT_ARGB32,
79 frame->width, frame->height,
80 frame->linesize[0]);
81 if (cairo_surface_status(image) != CAIRO_STATUS_SUCCESS)
82 return AVERROR_INVALIDDATA;
83
84 crender = cairo_create(image);
85
86 cairo_save(crender);
87 cairo_set_operator(crender, CAIRO_OPERATOR_CLEAR);
88 cairo_paint(crender);
89 cairo_restore(crender);
90
91 cairo_scale(crender, dimensions.width / (double)unscaled_dimensions.width,
92 dimensions.height / (double)unscaled_dimensions.height);
93
94 rsvg_handle_render_cairo(handle, crender);
95
96 cairo_destroy(crender);
97 cairo_surface_destroy(image);
98 g_object_unref(handle);
99
100 *got_frame = 1;
101
102 return 0;
103 }
104
105 #define OFFSET(x) offsetof(LibRSVGContext, x)
106 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
107 static const AVOption options[] = {
108 { "width", "Width to render to (0 for default)", OFFSET(width), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
109 { "height", "Height to render to (0 for default)", OFFSET(height), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
110 { "keep_ar", "Keep aspect ratio with custom width/height", OFFSET(keep_ar), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, DEC },
111 { NULL },
112 };
113
114 static const AVClass librsvg_decoder_class = {
115 .class_name = "Librsvg",
116 .item_name = av_default_item_name,
117 .option = options,
118 .version = LIBAVUTIL_VERSION_INT,
119 };
120
121 const FFCodec ff_librsvg_decoder = {
122 .p.name = "librsvg",
123 .p.long_name = NULL_IF_CONFIG_SMALL("Librsvg rasterizer"),
124 .p.priv_class = &librsvg_decoder_class,
125 .p.type = AVMEDIA_TYPE_VIDEO,
126 .p.id = AV_CODEC_ID_SVG,
127 .p.capabilities = AV_CODEC_CAP_DR1,
128 .p.wrapper_name = "librsvg",
129 FF_CODEC_DECODE_CB(librsvg_decode_frame),
130 .priv_data_size = sizeof(LibRSVGContext),
131 };
132