FFmpeg/libavcodec/librsvgdec.c
2017-05-16 12:51:52 +02:00

128 lines
4.4 KiB
C

/*
* Librsvg rasterization wrapper
* Copyright (c) 2017 Rostislav Pehlivanov <atomnuker@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avcodec.h"
#include "internal.h"
#include "libavutil/opt.h"
#include "librsvg-2.0/librsvg/rsvg.h"
typedef struct LibRSVGContext {
AVClass *class;
int width;
int height;
int keep_ar;
} LibRSVGContext;
static int librsvg_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *pkt)
{
int ret;
LibRSVGContext *s = avctx->priv_data;
AVFrame *frame = data;
RsvgHandle *handle;
RsvgDimensionData unscaled_dimensions, dimensions;
cairo_surface_t *image;
cairo_t *crender = NULL;
GError *error = NULL;
*got_frame = 0;
handle = rsvg_handle_new_from_data(pkt->data, pkt->size, &error);
if (error) {
av_log(avctx, AV_LOG_ERROR, "Error parsing svg!\n");
g_error_free(error);
return AVERROR_INVALIDDATA;
}
rsvg_handle_get_dimensions(handle, &dimensions);
rsvg_handle_get_dimensions(handle, &unscaled_dimensions);
dimensions.width = s->width ? s->width : dimensions.width;
dimensions.height = s->height ? s->height : dimensions.height;
if (s->keep_ar && (s->width || s->height)) {
double default_ar = unscaled_dimensions.width/(double)unscaled_dimensions.height;
if (!s->width)
dimensions.width = lrintf(dimensions.height * default_ar);
else
dimensions.height = lrintf(dimensions.width / default_ar);
}
if ((ret = ff_set_dimensions(avctx, dimensions.width, dimensions.height)))
return ret;
avctx->pix_fmt = AV_PIX_FMT_RGB32;
if ((ret = ff_get_buffer(avctx, frame, 0)))
return ret;
frame->pict_type = AV_PICTURE_TYPE_I;
frame->key_frame = 1;
image = cairo_image_surface_create_for_data(frame->data[0], CAIRO_FORMAT_ARGB32,
frame->width, frame->height,
frame->linesize[0]);
if (cairo_surface_status(image) != CAIRO_STATUS_SUCCESS)
return AVERROR_INVALIDDATA;
crender = cairo_create(image);
cairo_set_source_rgba(crender, 0.0, 0.0, 0.0, 1.0f);
cairo_paint_with_alpha(crender, 0.0f);
cairo_scale(crender, dimensions.width / (double)unscaled_dimensions.width,
dimensions.height / (double)unscaled_dimensions.height);
rsvg_handle_render_cairo(handle, crender);
cairo_destroy(crender);
cairo_surface_destroy(image);
g_object_unref(handle);
*got_frame = 1;
return 0;
}
#define OFFSET(x) offsetof(LibRSVGContext, x)
#define DEC (AV_OPT_FLAG_DECODING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
static const AVOption options[] = {
{ "width", "Width to render to (0 for default)", OFFSET(width), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
{ "height", "Height to render to (0 for default)", OFFSET(height), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, DEC },
{ "keep_ar", "Keep aspect ratio with custom width/height", OFFSET(keep_ar), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, DEC },
{ NULL },
};
static const AVClass librsvg_decoder_class = {
.class_name = "Librsvg",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVCodec ff_librsvg_decoder = {
.name = "librsvg",
.long_name = NULL_IF_CONFIG_SMALL("Librsvg rasterizer"),
.priv_class = &librsvg_decoder_class,
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_SVG,
.decode = librsvg_decode_frame,
.priv_data_size = sizeof(LibRSVGContext),
.capabilities = AV_CODEC_CAP_LOSSLESS | AV_CODEC_CAP_DR1,
};