libavfilter/vf_ass.c - third_party/ffmpeg - Git at Google

 /*
  * 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"

 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)

 static const AVOption ass_options[] = {
     {"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 },
     {NULL},
 };

 static const char *ass_get_name(void *ctx)
 {
     return "ass";
 }

 static const AVClass ass_class = {
     "AssContext",
     ass_get_name,
     ass_options
 };

 /* libass supports a log level ranging from 0 to 7 */
 int ass_libav_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_libav_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, void *opaque)
 {
     AssContext *ass = ctx->priv;
     int ret;

     ass->class = &ass_class;
     av_opt_set_defaults(ass);

     if (args)
         ass->filename = av_get_token(&args, ":");
     if (!ass->filename || !*ass->filename) {
         av_log(ctx, AV_LOG_ERROR, "No filename provided!\n");
         return AVERROR(EINVAL);
     }

     if (*args++ == ':' && (ret = av_set_options_string(ass, args, "=", ":")) < 0) {
         av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
         return ret;
     }

     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_freep(&ass->filename);
     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)
 {
     avfilter_set_common_pixel_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 void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }

 /* 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 void 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);

     avfilter_draw_slice(outlink, 0, picref->video->h, 1);
     avfilter_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 = avfilter_null_get_video_buffer,
           .start_frame      = avfilter_null_start_frame,
           .draw_slice       = null_draw_slice,
           .end_frame        = end_frame,
           .config_props     = config_input,
           .min_perms        = AV_PERM_WRITE | AV_PERM_READ,
           .rej_perms        = AV_PERM_PRESERVE },
         { .name = NULL}
     },
     .outputs = (const AVFilterPad[]) {
         { .name             = "default",
           .type             = AVMEDIA_TYPE_VIDEO, },
         { .name = NULL}
     },
 };
	/*
	* 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"

	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)

	static const AVOption ass_options[] = {
	{"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 },
	{NULL},
	};

	static const char ass_get_name(void ctx)
	{
	return "ass";
	}

	static const AVClass ass_class = {
	"AssContext",
	ass_get_name,
	ass_options
	};

	/* libass supports a log level ranging from 0 to 7 */
	int ass_libav_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_libav_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, void *opaque)
	{
	AssContext *ass = ctx->priv;
	int ret;

	ass->class = &ass_class;
	av_opt_set_defaults(ass);

	if (args)
	ass->filename = av_get_token(&args, ":");
	if (!ass->filename \|\| !*ass->filename) {
	av_log(ctx, AV_LOG_ERROR, "No filename provided!\n");
	return AVERROR(EINVAL);
	}

	if (*args++ == ':' && (ret = av_set_options_string(ass, args, "=", ":")) < 0) {
	av_log(ctx, AV_LOG_ERROR, "Error parsing options string: '%s'\n", args);
	return ret;
	}

	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_freep(&ass->filename);
	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)
	{
	avfilter_set_common_pixel_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 void null_draw_slice(AVFilterLink *link, int y, int h, int slice_dir) { }

	/* 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 void 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);

	avfilter_draw_slice(outlink, 0, picref->video->h, 1);
	avfilter_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 = avfilter_null_get_video_buffer,
	.start_frame = avfilter_null_start_frame,
	.draw_slice = null_draw_slice,
	.end_frame = end_frame,
	.config_props = config_input,
	.min_perms = AV_PERM_WRITE \| AV_PERM_READ,
	.rej_perms = AV_PERM_PRESERVE },
	{ .name = NULL}
	},
	.outputs = (const AVFilterPad[]) {
	{ .name = "default",
	.type = AVMEDIA_TYPE_VIDEO, },
	{ .name = NULL}
	},
	};