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 "internal.h"
24 #include "libavutil/opt.h"
25 #include "librsvg-2.0/librsvg/rsvg.h"
26 
27 typedef struct LibRSVGContext {
28  AVClass *class;
29 
30  int width;
31  int height;
32  int keep_ar;
34 
35 static int librsvg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *pkt)
36 {
37  int ret;
38  LibRSVGContext *s = avctx->priv_data;
39  AVFrame *frame = data;
40 
41  RsvgHandle *handle;
42  RsvgDimensionData unscaled_dimensions, dimensions;
43  cairo_surface_t *image;
44  cairo_t *crender = NULL;
45  GError *error = NULL;
46 
47  *got_frame = 0;
48 
49  handle = rsvg_handle_new_from_data(pkt->data, pkt->size, &error);
50  if (error) {
51  av_log(avctx, AV_LOG_ERROR, "Error parsing svg!\n");
52  g_error_free(error);
53  return AVERROR_INVALIDDATA;
54  }
55 
56  rsvg_handle_get_dimensions(handle, &dimensions);
57  rsvg_handle_get_dimensions(handle, &unscaled_dimensions);
58  dimensions.width = s->width ? s->width : dimensions.width;
59  dimensions.height = s->height ? s->height : dimensions.height;
60  if (s->keep_ar && (s->width || s->height)) {
61  double default_ar = unscaled_dimensions.width/(double)unscaled_dimensions.height;
62  if (!s->width)
63  dimensions.width = lrintf(dimensions.height * default_ar);
64  else
65  dimensions.height = lrintf(dimensions.width / default_ar);
66  }
67 
68  if ((ret = ff_set_dimensions(avctx, dimensions.width, dimensions.height)))
69  return ret;
70  avctx->pix_fmt = AV_PIX_FMT_RGB32;
71 
72  if ((ret = ff_get_buffer(avctx, frame, 0)))
73  return ret;
75  frame->key_frame = 1;
76 
77  image = cairo_image_surface_create_for_data(frame->data[0], CAIRO_FORMAT_ARGB32,
78  frame->width, frame->height,
79  frame->linesize[0]);
80  if (cairo_surface_status(image) != CAIRO_STATUS_SUCCESS)
81  return AVERROR_INVALIDDATA;
82 
83  crender = cairo_create(image);
84 
85  cairo_save(crender);
86  cairo_set_operator(crender, CAIRO_OPERATOR_CLEAR);
87  cairo_paint(crender);
88  cairo_restore(crender);
89 
90  cairo_scale(crender, dimensions.width / (double)unscaled_dimensions.width,
91  dimensions.height / (double)unscaled_dimensions.height);
92 
93  rsvg_handle_render_cairo(handle, crender);
94 
95  cairo_destroy(crender);
96  cairo_surface_destroy(image);
97  g_object_unref(handle);
98 
99  *got_frame = 1;
100 
101  return 0;
102 }
103 
104 #define OFFSET(x) offsetof(LibRSVGContext, x)
105 #define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
106 static const AVOption options[] = {
107  { "width", "Width to render to (0 for default)", OFFSET(width), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
108  { "height", "Height to render to (0 for default)", OFFSET(height), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
109  { "keep_ar", "Keep aspect ratio with custom width/height", OFFSET(keep_ar), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, DEC },
110  { NULL },
111 };
112 
114  .class_name = "Librsvg",
115  .item_name = av_default_item_name,
116  .option = options,
117  .version = LIBAVUTIL_VERSION_INT,
118 };
119 
121  .name = "librsvg",
122  .long_name = NULL_IF_CONFIG_SMALL("Librsvg rasterizer"),
123  .priv_class = &librsvg_decoder_class,
124  .type = AVMEDIA_TYPE_VIDEO,
125  .id = AV_CODEC_ID_SVG,
126  .decode = librsvg_decode_frame,
127  .priv_data_size = sizeof(LibRSVGContext),
128  .capabilities = AV_CODEC_CAP_LOSSLESS | AV_CODEC_CAP_DR1,
129  .wrapper_name = "librsvg",
130 };
#define NULL
Definition: coverity.c:32
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
AVOption.
Definition: opt.h:246
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
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:104
int size
Definition: avcodec.h:1478
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1775
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3481
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:72
AVOptions.
uint8_t * data
Definition: avcodec.h:1477
#define lrintf(x)
Definition: libm_mips.h:70
#define av_log(a,...)
int width
Definition: frame.h:353
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define OFFSET(x)
Definition: librsvgdec.c:104
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
#define DEC
Definition: librsvgdec.c:105
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
int width
picture width / height.
Definition: avcodec.h:1738
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
#define s(width, name)
Definition: cbs_vp9.c:257
static void error(const char *err)
if(ret)
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
main external API structure.
Definition: avcodec.h:1565
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:360
static const AVClass librsvg_decoder_class
Definition: librsvgdec.c:113
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
Describe the class of an AVClass context structure.
Definition: log.h:67
static const AVOption options[]
Definition: librsvgdec.c:106
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
AVCodec ff_librsvg_decoder
Definition: librsvgdec.c:120
#define AV_CODEC_CAP_LOSSLESS
Codec is lossless.
Definition: avcodec.h:1071
static int librsvg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *pkt)
Definition: librsvgdec.c:35
void * priv_data
Definition: avcodec.h:1592
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
int height
Definition: frame.h:353
This structure stores compressed data.
Definition: avcodec.h:1454
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981