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-rw-r--r--libavfilter/vf_ass.c228
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diff --git a/libavfilter/vf_ass.c b/libavfilter/vf_ass.c
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+/*
+ * Copyright (c) 2011 Baptiste Coudurier
+ * Copyright (c) 2011 Stefano Sabatini
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * Libass subtitles burning filter.
+ *
+ * @see{http://www.matroska.org/technical/specs/subtitles/ssa.html}
+ */
+
+#include <ass/ass.h>
+
+#include "libavutil/avstring.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "drawutils.h"
+#include "avfilter.h"
+#include "internal.h"
+#include "formats.h"
+#include "video.h"
+
+typedef struct {
+ const AVClass *class;
+ ASS_Library *library;
+ ASS_Renderer *renderer;
+ ASS_Track *track;
+ char *filename;
+ uint8_t rgba_map[4];
+ int pix_step[4]; ///< steps per pixel for each plane of the main output
+ int original_w, original_h;
+ FFDrawContext draw;
+} AssContext;
+
+#define OFFSET(x) offsetof(AssContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption ass_options[] = {
+ {"filename", "set the filename of the ASS file to read", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
+ {"f", "set the filename of the ASS file to read", OFFSET(filename), AV_OPT_TYPE_STRING, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
+ {"original_size", "set the size of the original video (used to scale fonts)", OFFSET(original_w), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, CHAR_MIN, CHAR_MAX, FLAGS },
+ {NULL},
+};
+
+AVFILTER_DEFINE_CLASS(ass);
+
+/* libass supports a log level ranging from 0 to 7 */
+static const int ass_libavfilter_log_level_map[] = {
+ AV_LOG_QUIET, /* 0 */
+ AV_LOG_PANIC, /* 1 */
+ AV_LOG_FATAL, /* 2 */
+ AV_LOG_ERROR, /* 3 */
+ AV_LOG_WARNING, /* 4 */
+ AV_LOG_INFO, /* 5 */
+ AV_LOG_VERBOSE, /* 6 */
+ AV_LOG_DEBUG, /* 7 */
+};
+
+static void ass_log(int ass_level, const char *fmt, va_list args, void *ctx)
+{
+ int level = ass_libavfilter_log_level_map[ass_level];
+
+ av_vlog(ctx, level, fmt, args);
+ av_log(ctx, level, "\n");
+}
+
+static av_cold int init(AVFilterContext *ctx, const char *args)
+{
+ AssContext *ass = ctx->priv;
+ static const char *shorthand[] = { "filename", NULL };
+ int ret;
+
+ ass->class = &ass_class;
+ av_opt_set_defaults(ass);
+
+ if ((ret = av_opt_set_from_string(ass, args, shorthand, "=", ":")) < 0)
+ return ret;
+
+ if (!ass->filename) {
+ av_log(ctx, AV_LOG_ERROR, "No filename provided!\n");
+ return AVERROR(EINVAL);
+ }
+
+ ass->library = ass_library_init();
+ if (!ass->library) {
+ av_log(ctx, AV_LOG_ERROR, "Could not initialize libass.\n");
+ return AVERROR(EINVAL);
+ }
+ ass_set_message_cb(ass->library, ass_log, ctx);
+
+ ass->renderer = ass_renderer_init(ass->library);
+ if (!ass->renderer) {
+ av_log(ctx, AV_LOG_ERROR, "Could not initialize libass renderer.\n");
+ return AVERROR(EINVAL);
+ }
+
+ ass->track = ass_read_file(ass->library, ass->filename, NULL);
+ if (!ass->track) {
+ av_log(ctx, AV_LOG_ERROR,
+ "Could not create a libass track when reading file '%s'\n",
+ ass->filename);
+ return AVERROR(EINVAL);
+ }
+
+ ass_set_fonts(ass->renderer, NULL, NULL, 1, NULL, 1);
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ AssContext *ass = ctx->priv;
+
+ av_opt_free(ass);
+ if (ass->track)
+ ass_free_track(ass->track);
+ if (ass->renderer)
+ ass_renderer_done(ass->renderer);
+ if (ass->library)
+ ass_library_done(ass->library);
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
+ return 0;
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+ AssContext *ass = inlink->dst->priv;
+
+ ff_draw_init(&ass->draw, inlink->format, 0);
+
+ ass_set_frame_size (ass->renderer, inlink->w, inlink->h);
+ if (ass->original_w && ass->original_h)
+ ass_set_aspect_ratio(ass->renderer, (double)inlink->w / inlink->h,
+ (double)ass->original_w / ass->original_h);
+
+ return 0;
+}
+
+static int null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { return 0; }
+
+/* libass stores an RGBA color in the format RRGGBBTT, where TT is the transparency level */
+#define AR(c) ( (c)>>24)
+#define AG(c) (((c)>>16)&0xFF)
+#define AB(c) (((c)>>8) &0xFF)
+#define AA(c) ((0xFF-c) &0xFF)
+
+static void overlay_ass_image(AssContext *ass, AVFilterBufferRef *picref,
+ const ASS_Image *image)
+{
+ for (; image; image = image->next) {
+ uint8_t rgba_color[] = {AR(image->color), AG(image->color), AB(image->color), AA(image->color)};
+ FFDrawColor color;
+ ff_draw_color(&ass->draw, &color, rgba_color);
+ ff_blend_mask(&ass->draw, &color,
+ picref->data, picref->linesize,
+ picref->video->w, picref->video->h,
+ image->bitmap, image->stride, image->w, image->h,
+ 3, 0, image->dst_x, image->dst_y);
+ }
+}
+
+static int end_frame(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ AssContext *ass = ctx->priv;
+ AVFilterBufferRef *picref = inlink->cur_buf;
+ int detect_change = 0;
+ double time_ms = picref->pts * av_q2d(inlink->time_base) * 1000;
+ ASS_Image *image = ass_render_frame(ass->renderer, ass->track,
+ time_ms, &detect_change);
+
+ if (detect_change)
+ av_log(ctx, AV_LOG_DEBUG, "Change happened at time ms:%f\n", time_ms);
+
+ overlay_ass_image(ass, picref, image);
+
+ ff_draw_slice(outlink, 0, picref->video->h, 1);
+ return ff_end_frame(outlink);
+}
+
+AVFilter avfilter_vf_ass = {
+ .name = "ass",
+ .description = NULL_IF_CONFIG_SMALL("Render subtitles onto input video using the libass library."),
+ .priv_size = sizeof(AssContext),
+ .init = init,
+ .uninit = uninit,
+ .query_formats = query_formats,
+
+ .inputs = (const AVFilterPad[]) {
+ { .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .get_video_buffer = ff_null_get_video_buffer,
+ .start_frame = ff_null_start_frame,
+ .draw_slice = null_draw_slice,
+ .end_frame = end_frame,
+ .config_props = config_input,
+ .min_perms = AV_PERM_WRITE | AV_PERM_READ },
+ { .name = NULL}
+ },
+ .outputs = (const AVFilterPad[]) {
+ { .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO, },
+ { .name = NULL}
+ },
+ .priv_class = &ass_class,
+};
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