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

 /*
  * Copyright (c) 2010 Brandon Mintern
  * Copyright (c) 2007 Bobby Bingham
  *
  * 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
  * video fade filter
  * based heavily on vf_negate.c by Bobby Bingham
  */

 #include "libavutil/avstring.h"
 #include "libavutil/eval.h"
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "avfilter.h"
 #include "drawutils.h"
 #include "internal.h"

 #define R 0
 #define G 1
 #define B 2
 #define A 3

 #define Y 0
 #define U 1
 #define V 2

 typedef struct {
     const AVClass *class;
     int factor, fade_per_frame;
     unsigned int frame_index, start_frame, stop_frame, nb_frames;
     int hsub, vsub, bpp;
     unsigned int black_level, black_level_scaled;
     uint8_t is_packed_rgb;
     uint8_t rgba_map[4];
     int alpha;

     char *type;
 } FadeContext;

 #define OFFSET(x) offsetof(FadeContext, x)

 static const AVOption fade_options[] = {
     { "type",        "set the fade direction",                     OFFSET(type),        AV_OPT_TYPE_STRING, {.str = "in" }, CHAR_MIN, CHAR_MAX },
     { "t",           "set the fade direction",                     OFFSET(type),        AV_OPT_TYPE_STRING, {.str = "in" }, CHAR_MIN, CHAR_MAX },
     { "start_frame", "set expression of frame to start fading",    OFFSET(start_frame), AV_OPT_TYPE_INT, {.dbl = 0    }, 0, INT_MAX },
     { "s",           "set expression of frame to start fading",    OFFSET(start_frame), AV_OPT_TYPE_INT, {.dbl = 0    }, 0, INT_MAX },
     { "nb_frames",   "set expression for fade duration in frames", OFFSET(nb_frames),   AV_OPT_TYPE_INT, {.dbl = 25   }, 0, INT_MAX },
     { "n",           "set expression for fade duration in frames", OFFSET(nb_frames),   AV_OPT_TYPE_INT, {.dbl = 25   }, 0, INT_MAX },
     { "alpha",       "fade alpha if it is available on the input", OFFSET(alpha),       AV_OPT_TYPE_INT, {.dbl = 0    }, 0,       1 },
     {NULL},
 };

 static const char *fade_get_name(void *ctx)
 {
     return "fade";
 }

 static const AVClass fade_class = {
     "FadeContext",
     fade_get_name,
     fade_options
 };

 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
 {
     FadeContext *fade = ctx->priv;
     int ret = 0;
     char *args1, *expr, *bufptr = NULL;

     fade->class = &fade_class;
     av_opt_set_defaults(fade);

     if (!(args1 = av_strdup(args))) {
         ret = AVERROR(ENOMEM);
         goto end;
     }

     if (expr = av_strtok(args1, ":", &bufptr)) {
         if (!(fade->type = av_strdup(expr))) {
             ret = AVERROR(ENOMEM);
             goto end;
         }
     }
     if (expr = av_strtok(NULL, ":", &bufptr)) {
         if ((ret = av_opt_set(fade, "start_frame", expr, 0)) < 0) {
             av_log(ctx, AV_LOG_ERROR,
                    "Invalid value '%s' for start_frame option\n", expr);
             goto end;
         }
     }
     if (expr = av_strtok(NULL, ":", &bufptr)) {
         if ((ret = av_opt_set(fade, "nb_frames", expr, 0)) < 0) {
             av_log(ctx, AV_LOG_ERROR,
                    "Invalid value '%s' for nb_frames option\n", expr);
             goto end;
         }
     }

     if (bufptr && (ret = av_set_options_string(fade, bufptr, "=", ":")) < 0)
         goto end;

     fade->fade_per_frame = (1 << 16) / fade->nb_frames;
     if (!strcmp(fade->type, "in"))
         fade->factor = 0;
     else if (!strcmp(fade->type, "out")) {
         fade->fade_per_frame = -fade->fade_per_frame;
         fade->factor = (1 << 16);
     } else {
         av_log(ctx, AV_LOG_ERROR,
                "Type argument must be 'in' or 'out' but '%s' was specified\n", fade->type);
         ret = AVERROR(EINVAL);
         goto end;
     }
     fade->stop_frame = fade->start_frame + fade->nb_frames;

     av_log(ctx, AV_LOG_INFO,
            "type:%s start_frame:%d nb_frames:%d alpha:%d\n",
            fade->type, fade->start_frame, fade->nb_frames, fade->alpha);

 end:
     av_free(args1);
     return ret;
 }

 static av_cold void uninit(AVFilterContext *ctx)
 {
     FadeContext *fade = ctx->priv;

     av_freep(&fade->type);
 }

 static int query_formats(AVFilterContext *ctx)
 {
     static const enum PixelFormat pix_fmts[] = {
         PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P,
         PIX_FMT_YUV411P,  PIX_FMT_YUV410P,
         PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,
         PIX_FMT_YUV440P,  PIX_FMT_YUVJ440P,
         PIX_FMT_YUVA420P,
         PIX_FMT_RGB24,    PIX_FMT_BGR24,
         PIX_FMT_ARGB,     PIX_FMT_ABGR,
         PIX_FMT_RGBA,     PIX_FMT_BGRA,
         PIX_FMT_NONE
     };

     avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
     return 0;
 }

 const static enum PixelFormat studio_level_pix_fmts[] = {
     PIX_FMT_YUV444P,  PIX_FMT_YUV422P,  PIX_FMT_YUV420P,
     PIX_FMT_YUV411P,  PIX_FMT_YUV410P,
     PIX_FMT_YUV440P,
     PIX_FMT_NONE
 };

 static enum PixelFormat alpha_pix_fmts[] = {
     PIX_FMT_YUVA420P,
     PIX_FMT_ARGB, PIX_FMT_ABGR,
     PIX_FMT_RGBA, PIX_FMT_BGRA,
     PIX_FMT_NONE
 };

 static int config_props(AVFilterLink *inlink)
 {
     FadeContext *fade = inlink->dst->priv;
     const AVPixFmtDescriptor *pixdesc = &av_pix_fmt_descriptors[inlink->format];

     fade->hsub = pixdesc->log2_chroma_w;
     fade->vsub = pixdesc->log2_chroma_h;

     fade->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
     fade->alpha = fade->alpha ? ff_fmt_is_in(inlink->format, alpha_pix_fmts) : 0;
     fade->is_packed_rgb = ff_fill_rgba_map(fade->rgba_map, inlink->format) >= 0;

     /* use CCIR601/709 black level for studio-level pixel non-alpha components */
     fade->black_level =
             ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !fade->alpha ? 16 : 0;
     /* 32768 = 1 << 15, it is an integer representation
      * of 0.5 and is for rounding. */
     fade->black_level_scaled = (fade->black_level << 16) + 32768;
     return 0;
 }

 static void fade_plane(int y, int h, int w,
                        int fade_factor, int black_level, int black_level_scaled,
                        uint8_t offset, uint8_t step, int bytes_per_plane,
                        uint8_t *data, int line_size)
 {
     uint8_t *p;
     int i, j;

     /* luma, alpha or rgb plane */
     for (i = 0; i < h; i++) {
         p = data + offset + (y+i) * line_size;
         for (j = 0; j < w * bytes_per_plane; j++) {
             /* fade->factor is using 16 lower-order bits for decimal places. */
             *p = ((*p - black_level) * fade_factor + black_level_scaled) >> 16;
             p+=step;
         }
     }
 }

 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
 {
     FadeContext *fade = inlink->dst->priv;
     AVFilterBufferRef *outpic = inlink->cur_buf;
     uint8_t *p;
     int i, j, plane;

     if (fade->factor < UINT16_MAX) {
         if (fade->alpha) {
             // alpha only
             plane = fade->is_packed_rgb ? 0 : A; // alpha is on plane 0 for packed formats
                                                  // or plane 3 for planar formats
             fade_plane(y, h, inlink->w,
                        fade->factor, fade->black_level, fade->black_level_scaled,
                        fade->is_packed_rgb ? fade->rgba_map[A] : 0, // alpha offset for packed formats
                        fade->is_packed_rgb ? 4 : 1,                 // pixstep for 8 bit packed formats
                        1, outpic->data[plane], outpic->linesize[plane]);
         } else {
             /* luma or rgb plane */
             fade_plane(y, h, inlink->w,
                        fade->factor, fade->black_level, fade->black_level_scaled,
                        0, 1, // offset & pixstep for Y plane or RGB packed format
                        fade->bpp, outpic->data[0], outpic->linesize[0]);
             if (outpic->data[1] && outpic->data[2]) {
                 /* chroma planes */
                 for (plane = 1; plane < 3; plane++) {
                     for (i = 0; i < h; i++) {
                         p = outpic->data[plane] + ((y+i) >> fade->vsub) * outpic->linesize[plane];
                         for (j = 0; j < inlink->w >> fade->hsub; j++) {
                             /* 8421367 = ((128 << 1) + 1) << 15. It is an integer
                              * representation of 128.5. The .5 is for rounding
                              * purposes. */
                             *p = ((*p - 128) * fade->factor + 8421367) >> 16;
                             p++;
                         }
                     }
                 }
             }
         }
     }

     avfilter_draw_slice(inlink->dst->outputs[0], y, h, slice_dir);
 }

 static void end_frame(AVFilterLink *inlink)
 {
     FadeContext *fade = inlink->dst->priv;

     avfilter_end_frame(inlink->dst->outputs[0]);

     if (fade->frame_index >= fade->start_frame &&
         fade->frame_index <= fade->stop_frame)
         fade->factor += fade->fade_per_frame;
     fade->factor = av_clip_uint16(fade->factor);
     fade->frame_index++;
 }

 AVFilter avfilter_vf_fade = {
     .name          = "fade",
     .description   = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
     .init          = init,
     .uninit        = uninit,
     .priv_size     = sizeof(FadeContext),
     .query_formats = query_formats,

     .inputs    = (const AVFilterPad[]) {{ .name      = "default",
                                     .type            = AVMEDIA_TYPE_VIDEO,
                                     .config_props    = config_props,
                                     .get_video_buffer = avfilter_null_get_video_buffer,
                                     .start_frame      = avfilter_null_start_frame,
                                     .draw_slice      = draw_slice,
                                     .end_frame       = end_frame,
                                     .min_perms       = AV_PERM_READ | AV_PERM_WRITE,
                                     .rej_perms       = AV_PERM_PRESERVE, },
                                   { .name = NULL}},
     .outputs   = (const AVFilterPad[]) {{ .name      = "default",
                                     .type            = AVMEDIA_TYPE_VIDEO, },
                                   { .name = NULL}},
 };
	/*
	* Copyright (c) 2010 Brandon Mintern
	* Copyright (c) 2007 Bobby Bingham
	*
	* 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
	* video fade filter
	* based heavily on vf_negate.c by Bobby Bingham
	*/

	#include "libavutil/avstring.h"
	#include "libavutil/eval.h"
	#include "libavutil/opt.h"
	#include "libavutil/pixdesc.h"
	#include "avfilter.h"
	#include "drawutils.h"
	#include "internal.h"

	#define R 0
	#define G 1
	#define B 2
	#define A 3

	#define Y 0
	#define U 1
	#define V 2

	typedef struct {
	const AVClass *class;
	int factor, fade_per_frame;
	unsigned int frame_index, start_frame, stop_frame, nb_frames;
	int hsub, vsub, bpp;
	unsigned int black_level, black_level_scaled;
	uint8_t is_packed_rgb;
	uint8_t rgba_map[4];
	int alpha;

	char *type;
	} FadeContext;

	#define OFFSET(x) offsetof(FadeContext, x)

	static const AVOption fade_options[] = {
	{ "type", "set the fade direction", OFFSET(type), AV_OPT_TYPE_STRING, {.str = "in" }, CHAR_MIN, CHAR_MAX },
	{ "t", "set the fade direction", OFFSET(type), AV_OPT_TYPE_STRING, {.str = "in" }, CHAR_MIN, CHAR_MAX },
	{ "start_frame", "set expression of frame to start fading", OFFSET(start_frame), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX },
	{ "s", "set expression of frame to start fading", OFFSET(start_frame), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX },
	{ "nb_frames", "set expression for fade duration in frames", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.dbl = 25 }, 0, INT_MAX },
	{ "n", "set expression for fade duration in frames", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.dbl = 25 }, 0, INT_MAX },
	{ "alpha", "fade alpha if it is available on the input", OFFSET(alpha), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, 1 },
	{NULL},
	};

	static const char fade_get_name(void ctx)
	{
	return "fade";
	}

	static const AVClass fade_class = {
	"FadeContext",
	fade_get_name,
	fade_options
	};

	static av_cold int init(AVFilterContext ctx, const char args, void *opaque)
	{
	FadeContext *fade = ctx->priv;
	int ret = 0;
	char args1, expr, *bufptr = NULL;

	fade->class = &fade_class;
	av_opt_set_defaults(fade);

	if (!(args1 = av_strdup(args))) {
	ret = AVERROR(ENOMEM);
	goto end;
	}

	if (expr = av_strtok(args1, ":", &bufptr)) {
	if (!(fade->type = av_strdup(expr))) {
	ret = AVERROR(ENOMEM);
	goto end;
	}
	}
	if (expr = av_strtok(NULL, ":", &bufptr)) {
	if ((ret = av_opt_set(fade, "start_frame", expr, 0)) < 0) {
	av_log(ctx, AV_LOG_ERROR,
	"Invalid value '%s' for start_frame option\n", expr);
	goto end;
	}
	}
	if (expr = av_strtok(NULL, ":", &bufptr)) {
	if ((ret = av_opt_set(fade, "nb_frames", expr, 0)) < 0) {
	av_log(ctx, AV_LOG_ERROR,
	"Invalid value '%s' for nb_frames option\n", expr);
	goto end;
	}
	}

	if (bufptr && (ret = av_set_options_string(fade, bufptr, "=", ":")) < 0)
	goto end;

	fade->fade_per_frame = (1 << 16) / fade->nb_frames;
	if (!strcmp(fade->type, "in"))
	fade->factor = 0;
	else if (!strcmp(fade->type, "out")) {
	fade->fade_per_frame = -fade->fade_per_frame;
	fade->factor = (1 << 16);
	} else {
	av_log(ctx, AV_LOG_ERROR,
	"Type argument must be 'in' or 'out' but '%s' was specified\n", fade->type);
	ret = AVERROR(EINVAL);
	goto end;
	}
	fade->stop_frame = fade->start_frame + fade->nb_frames;

	av_log(ctx, AV_LOG_INFO,
	"type:%s start_frame:%d nb_frames:%d alpha:%d\n",
	fade->type, fade->start_frame, fade->nb_frames, fade->alpha);

	end:
	av_free(args1);
	return ret;
	}

	static av_cold void uninit(AVFilterContext *ctx)
	{
	FadeContext *fade = ctx->priv;

	av_freep(&fade->type);
	}

	static int query_formats(AVFilterContext *ctx)
	{
	static const enum PixelFormat pix_fmts[] = {
	PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P,
	PIX_FMT_YUV411P, PIX_FMT_YUV410P,
	PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P,
	PIX_FMT_YUV440P, PIX_FMT_YUVJ440P,
	PIX_FMT_YUVA420P,
	PIX_FMT_RGB24, PIX_FMT_BGR24,
	PIX_FMT_ARGB, PIX_FMT_ABGR,
	PIX_FMT_RGBA, PIX_FMT_BGRA,
	PIX_FMT_NONE
	};

	avfilter_set_common_pixel_formats(ctx, avfilter_make_format_list(pix_fmts));
	return 0;
	}

	const static enum PixelFormat studio_level_pix_fmts[] = {
	PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P,
	PIX_FMT_YUV411P, PIX_FMT_YUV410P,
	PIX_FMT_YUV440P,
	PIX_FMT_NONE
	};

	static enum PixelFormat alpha_pix_fmts[] = {
	PIX_FMT_YUVA420P,
	PIX_FMT_ARGB, PIX_FMT_ABGR,
	PIX_FMT_RGBA, PIX_FMT_BGRA,
	PIX_FMT_NONE
	};

	static int config_props(AVFilterLink *inlink)
	{
	FadeContext *fade = inlink->dst->priv;
	const AVPixFmtDescriptor *pixdesc = &av_pix_fmt_descriptors[inlink->format];

	fade->hsub = pixdesc->log2_chroma_w;
	fade->vsub = pixdesc->log2_chroma_h;

	fade->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
	fade->alpha = fade->alpha ? ff_fmt_is_in(inlink->format, alpha_pix_fmts) : 0;
	fade->is_packed_rgb = ff_fill_rgba_map(fade->rgba_map, inlink->format) >= 0;

	/* use CCIR601/709 black level for studio-level pixel non-alpha components */
	fade->black_level =
	ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !fade->alpha ? 16 : 0;
	/* 32768 = 1 << 15, it is an integer representation
	* of 0.5 and is for rounding. */
	fade->black_level_scaled = (fade->black_level << 16) + 32768;
	return 0;
	}

	static void fade_plane(int y, int h, int w,
	int fade_factor, int black_level, int black_level_scaled,
	uint8_t offset, uint8_t step, int bytes_per_plane,
	uint8_t *data, int line_size)
	{
	uint8_t *p;
	int i, j;

	/* luma, alpha or rgb plane */
	for (i = 0; i < h; i++) {
	p = data + offset + (y+i) * line_size;
	for (j = 0; j < w * bytes_per_plane; j++) {
	/* fade->factor is using 16 lower-order bits for decimal places. */
	p = ((p - black_level) * fade_factor + black_level_scaled) >> 16;
	p+=step;
	}
	}
	}

	static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
	{
	FadeContext *fade = inlink->dst->priv;
	AVFilterBufferRef *outpic = inlink->cur_buf;
	uint8_t *p;
	int i, j, plane;

	if (fade->factor < UINT16_MAX) {
	if (fade->alpha) {
	// alpha only
	plane = fade->is_packed_rgb ? 0 : A; // alpha is on plane 0 for packed formats
	// or plane 3 for planar formats
	fade_plane(y, h, inlink->w,
	fade->factor, fade->black_level, fade->black_level_scaled,
	fade->is_packed_rgb ? fade->rgba_map[A] : 0, // alpha offset for packed formats
	fade->is_packed_rgb ? 4 : 1, // pixstep for 8 bit packed formats
	1, outpic->data[plane], outpic->linesize[plane]);
	} else {
	/* luma or rgb plane */
	fade_plane(y, h, inlink->w,
	fade->factor, fade->black_level, fade->black_level_scaled,
	0, 1, // offset & pixstep for Y plane or RGB packed format
	fade->bpp, outpic->data[0], outpic->linesize[0]);
	if (outpic->data[1] && outpic->data[2]) {
	/* chroma planes */
	for (plane = 1; plane < 3; plane++) {
	for (i = 0; i < h; i++) {
	p = outpic->data[plane] + ((y+i) >> fade->vsub) * outpic->linesize[plane];
	for (j = 0; j < inlink->w >> fade->hsub; j++) {
	/* 8421367 = ((128 << 1) + 1) << 15. It is an integer
	* representation of 128.5. The .5 is for rounding
	* purposes. */
	p = ((p - 128) * fade->factor + 8421367) >> 16;
	p++;
	}
	}
	}
	}
	}
	}

	avfilter_draw_slice(inlink->dst->outputs[0], y, h, slice_dir);
	}

	static void end_frame(AVFilterLink *inlink)
	{
	FadeContext *fade = inlink->dst->priv;

	avfilter_end_frame(inlink->dst->outputs[0]);

	if (fade->frame_index >= fade->start_frame &&
	fade->frame_index <= fade->stop_frame)
	fade->factor += fade->fade_per_frame;
	fade->factor = av_clip_uint16(fade->factor);
	fade->frame_index++;
	}

	AVFilter avfilter_vf_fade = {
	.name = "fade",
	.description = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
	.init = init,
	.uninit = uninit,
	.priv_size = sizeof(FadeContext),
	.query_formats = query_formats,

	.inputs = (const AVFilterPad[]) {{ .name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.config_props = config_props,
	.get_video_buffer = avfilter_null_get_video_buffer,
	.start_frame = avfilter_null_start_frame,
	.draw_slice = draw_slice,
	.end_frame = end_frame,
	.min_perms = AV_PERM_READ \| AV_PERM_WRITE,
	.rej_perms = AV_PERM_PRESERVE, },
	{ .name = NULL}},
	.outputs = (const AVFilterPad[]) {{ .name = "default",
	.type = AVMEDIA_TYPE_VIDEO, },
	{ .name = NULL}},
	};