FFmpeg
librsvgdec.c
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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 "decode.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;
35 
37  int *got_frame, AVPacket *pkt)
38 {
39  int ret;
40  LibRSVGContext *s = avctx->priv_data;
41  RsvgHandle *handle = NULL;
42  RsvgDimensionData dimensions;
43 #if LIBRSVG_MAJOR_VERSION > 2 || LIBRSVG_MAJOR_VERSION == 2 && LIBRSVG_MINOR_VERSION >= 52
44  RsvgRectangle viewport = { 0 };
45 #else
46  RsvgDimensionData unscaled_dimensions;
47 #endif
48  cairo_surface_t *image = NULL;
49  cairo_t *crender = NULL;
50  GError *error = NULL;
51  gboolean gret;
52 
53  *got_frame = 0;
54 
55  handle = rsvg_handle_new_from_data(pkt->data, pkt->size, &error);
56  if (error) {
57  av_log(avctx, AV_LOG_ERROR, "Error parsing svg: %s\n", error->message);
59  goto end;
60  }
61 
62 #if LIBRSVG_MAJOR_VERSION > 2 || LIBRSVG_MAJOR_VERSION == 2 && LIBRSVG_MINOR_VERSION >= 52
63  gret = rsvg_handle_get_intrinsic_size_in_pixels(handle, &viewport.width, &viewport.height);
64  if (!gret) {
65  viewport.width = s->width ? s->width : 100;
66  viewport.height = s->height ? s->height : 100;
67  }
68  dimensions.width = (int)viewport.width;
69  dimensions.height = (int)viewport.height;
70 #else
71  rsvg_handle_get_dimensions(handle, &dimensions);
72  rsvg_handle_get_dimensions(handle, &unscaled_dimensions);
73 #endif
74  dimensions.width = s->width ? s->width : dimensions.width;
75  dimensions.height = s->height ? s->height : dimensions.height;
76  if (s->keep_ar && (s->width || s->height)) {
77 #if LIBRSVG_MAJOR_VERSION > 2 || LIBRSVG_MAJOR_VERSION == 2 && LIBRSVG_MINOR_VERSION >= 52
78  double default_ar = viewport.width / viewport.height;
79 #else
80  double default_ar = unscaled_dimensions.width/(double)unscaled_dimensions.height;
81 #endif
82  if (!s->width)
83  dimensions.width = lrintf(dimensions.height * default_ar);
84  else
85  dimensions.height = lrintf(dimensions.width / default_ar);
86  }
87 
88  ret = ff_set_dimensions(avctx, dimensions.width, dimensions.height);
89  if (ret < 0)
90  goto end;
91 
92  avctx->pix_fmt = AV_PIX_FMT_RGB32;
93  viewport.width = dimensions.width;
94  viewport.height = dimensions.height;
95 
96  ret = ff_get_buffer(avctx, frame, 0);
97  if (ret < 0)
98  goto end;
99 
100  frame->pict_type = AV_PICTURE_TYPE_I;
101  frame->flags |= AV_FRAME_FLAG_KEY;
102 
103  image = cairo_image_surface_create_for_data(frame->data[0], CAIRO_FORMAT_ARGB32,
104  frame->width, frame->height,
105  frame->linesize[0]);
106  if (cairo_surface_status(image) != CAIRO_STATUS_SUCCESS) {
108  goto end;
109  }
110 
111  crender = cairo_create(image);
112 
113  cairo_save(crender);
114  cairo_set_operator(crender, CAIRO_OPERATOR_CLEAR);
115  cairo_paint(crender);
116  cairo_restore(crender);
117 
118 #if LIBRSVG_MAJOR_VERSION > 2 || LIBRSVG_MAJOR_VERSION == 2 && LIBRSVG_MINOR_VERSION >= 52
119  gret = rsvg_handle_render_document(handle, crender, &viewport, &error);
120 #else
121  cairo_scale(crender, dimensions.width / (double)unscaled_dimensions.width,
122  dimensions.height / (double)unscaled_dimensions.height);
123  gret = rsvg_handle_render_cairo(handle, crender);
124 #endif
125 
126  if (!gret) {
127  av_log(avctx, AV_LOG_ERROR, "Error rendering svg: %s\n", error ? error->message : "unknown error");
129  goto end;
130  }
131 
132  *got_frame = 1;
133  ret = 0;
134 
135 end:
136  if (error)
137  g_error_free(error);
138  if (handle)
139  g_object_unref(handle);
140  if (crender)
141  cairo_destroy(crender);
142  if (image)
143  cairo_surface_destroy(image);
144 
145  return ret;
146 }
147 
148 #define OFFSET(x) offsetof(LibRSVGContext, x)
149 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
150 static const AVOption options[] = {
151  { "width", "Width to render to (0 for default)", OFFSET(width), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
152  { "height", "Height to render to (0 for default)", OFFSET(height), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
153  { "keep_ar", "Keep aspect ratio with custom width/height", OFFSET(keep_ar), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, DEC },
154  { NULL },
155 };
156 
158  .class_name = "Librsvg",
159  .item_name = av_default_item_name,
160  .option = options,
161  .version = LIBAVUTIL_VERSION_INT,
162 };
163 
165  .p.name = "librsvg",
166  CODEC_LONG_NAME("Librsvg rasterizer"),
167  .p.priv_class = &librsvg_decoder_class,
168  .p.type = AVMEDIA_TYPE_VIDEO,
169  .p.id = AV_CODEC_ID_SVG,
170  .p.capabilities = AV_CODEC_CAP_DR1,
171  .p.wrapper_name = "librsvg",
173  .priv_data_size = sizeof(LibRSVGContext),
174 };
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:32
opt.h
LibRSVGContext::width
int width
Definition: librsvgdec.c:31
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:374
AVPacket::data
uint8_t * data
Definition: packet.h:524
AVOption
AVOption.
Definition: opt.h:357
FFCodec
Definition: codec_internal.h:126
ff_set_dimensions
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:94
options
static const AVOption options[]
Definition: librsvgdec.c:150
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:130
librsvg_decoder_class
static const AVClass librsvg_decoder_class
Definition: librsvgdec.c:157
pkt
AVPacket * pkt
Definition: movenc.c:60
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:180
AV_FRAME_FLAG_KEY
#define AV_FRAME_FLAG_KEY
A flag to mark frames that are keyframes.
Definition: frame.h:625
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:286
s
#define s(width, name)
Definition: cbs_vp9.c:198
LibRSVGContext
Definition: librsvgdec.c:28
ff_librsvg_decoder
const FFCodec ff_librsvg_decoder
Definition: librsvgdec.c:164
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:271
librsvg_decode_frame
static int librsvg_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *pkt)
Definition: librsvgdec.c:36
if
if(ret)
Definition: filter_design.txt:179
LibRSVGContext::height
int height
Definition: librsvgdec.c:32
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
NULL
#define NULL
Definition: coverity.c:32
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:237
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:279
double
double
Definition: af_crystalizer.c:131
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1575
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:525
codec_internal.h
height
#define height
AV_PIX_FMT_RGB32
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:451
AVERROR_EXTERNAL
#define AVERROR_EXTERNAL
Generic error in an external library.
Definition: error.h:59
AV_CODEC_ID_SVG
@ AV_CODEC_ID_SVG
Definition: codec_id.h:284
lrintf
#define lrintf(x)
Definition: libm_mips.h:72
OFFSET
#define OFFSET(x)
Definition: librsvgdec.c:148
LibRSVGContext::keep_ar
int keep_ar
Definition: librsvgdec.c:33
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:657
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:71
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext
main external API structure.
Definition: avcodec.h:445
AV_OPT_TYPE_INT
@ AV_OPT_TYPE_INT
Definition: opt.h:245
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:472
AVPacket
This structure stores compressed data.
Definition: packet.h:501
AV_OPT_TYPE_BOOL
@ AV_OPT_TYPE_BOOL
Definition: opt.h:261
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:618
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:27
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
int
int
Definition: ffmpeg_filter.c:424
DEC
#define DEC
Definition: librsvgdec.c:149