libavfilter/vf_framepack.c - manifest_repos/ffmpeg - Git at Google

 /*
  * Copyright (c) 2013 Vittorio Giovara
  *
  * 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
  * Generate a frame packed video, by combining two views in a single surface.
  */

 #include <string.h>

 #include "libavutil/common.h"
 #include "libavutil/imgutils.h"
 #include "libavutil/opt.h"
 #include "libavutil/pixdesc.h"
 #include "libavutil/rational.h"
 #include "libavutil/stereo3d.h"

 #include "avfilter.h"
 #include "filters.h"
 #include "formats.h"
 #include "internal.h"
 #include "video.h"

 #define LEFT  0
 #define RIGHT 1

 typedef struct FramepackContext {
     const AVClass *class;

     const AVPixFmtDescriptor *pix_desc; ///< agreed pixel format

     enum AVStereo3DType format;         ///< frame pack type output

     AVFrame *input_views[2];            ///< input frames
 } FramepackContext;

 static const enum AVPixelFormat formats_supported[] = {
     AV_PIX_FMT_YUV420P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV444P,
     AV_PIX_FMT_YUV410P,  AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVJ420P,
     AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
     AV_PIX_FMT_NONE
 };

 static int query_formats(AVFilterContext *ctx)
 {
     // this will ensure that formats are the same on all pads
     AVFilterFormats *fmts_list = ff_make_format_list(formats_supported);
     if (!fmts_list)
         return AVERROR(ENOMEM);
     return ff_set_common_formats(ctx, fmts_list);
 }

 static av_cold void framepack_uninit(AVFilterContext *ctx)
 {
     FramepackContext *s = ctx->priv;

     // clean any leftover frame
     av_frame_free(&s->input_views[LEFT]);
     av_frame_free(&s->input_views[RIGHT]);
 }

 static int config_output(AVFilterLink *outlink)
 {
     AVFilterContext *ctx  = outlink->src;
     FramepackContext *s   = outlink->src->priv;

     int width             = ctx->inputs[LEFT]->w;
     int height            = ctx->inputs[LEFT]->h;
     AVRational time_base  = ctx->inputs[LEFT]->time_base;
     AVRational frame_rate = ctx->inputs[LEFT]->frame_rate;

     // check size and fps match on the other input
     if (width  != ctx->inputs[RIGHT]->w ||
         height != ctx->inputs[RIGHT]->h) {
         av_log(ctx, AV_LOG_ERROR,
                "Left and right sizes differ (%dx%d vs %dx%d).\n",
                width, height,
                ctx->inputs[RIGHT]->w, ctx->inputs[RIGHT]->h);
         return AVERROR_INVALIDDATA;
     } else if (av_cmp_q(time_base, ctx->inputs[RIGHT]->time_base) != 0) {
         av_log(ctx, AV_LOG_ERROR,
                "Left and right time bases differ (%d/%d vs %d/%d).\n",
                time_base.num, time_base.den,
                ctx->inputs[RIGHT]->time_base.num,
                ctx->inputs[RIGHT]->time_base.den);
         return AVERROR_INVALIDDATA;
     } else if (av_cmp_q(frame_rate, ctx->inputs[RIGHT]->frame_rate) != 0) {
         av_log(ctx, AV_LOG_ERROR,
                "Left and right framerates differ (%d/%d vs %d/%d).\n",
                frame_rate.num, frame_rate.den,
                ctx->inputs[RIGHT]->frame_rate.num,
                ctx->inputs[RIGHT]->frame_rate.den);
         return AVERROR_INVALIDDATA;
     }

     s->pix_desc = av_pix_fmt_desc_get(outlink->format);
     if (!s->pix_desc)
         return AVERROR_BUG;

     // modify output properties as needed
     switch (s->format) {
     case AV_STEREO3D_FRAMESEQUENCE:
         time_base.den  *= 2;
         frame_rate.num *= 2;
         break;
     case AV_STEREO3D_COLUMNS:
     case AV_STEREO3D_SIDEBYSIDE:
         width *= 2;
         break;
     case AV_STEREO3D_LINES:
     case AV_STEREO3D_TOPBOTTOM:
         height *= 2;
         break;
     default:
         av_log(ctx, AV_LOG_ERROR, "Unknown packing mode.");
         return AVERROR_INVALIDDATA;
     }

     outlink->w          = width;
     outlink->h          = height;
     outlink->time_base  = time_base;
     outlink->frame_rate = frame_rate;

     return 0;
 }

 static void horizontal_frame_pack(AVFilterLink *outlink,
                                   AVFrame *out,
                                   int interleaved)
 {
     AVFilterContext *ctx = outlink->src;
     FramepackContext *s = ctx->priv;
     int i, plane;

     if (interleaved) {
         const uint8_t *leftp  = s->input_views[LEFT]->data[0];
         const uint8_t *rightp = s->input_views[RIGHT]->data[0];
         uint8_t *dstp         = out->data[0];
         int length = out->width / 2;
         int lines  = out->height;

         for (plane = 0; plane < s->pix_desc->nb_components; plane++) {
             if (plane == 1 || plane == 2) {
                 length = AV_CEIL_RSHIFT(out->width / 2, s->pix_desc->log2_chroma_w);
                 lines  = AV_CEIL_RSHIFT(out->height,    s->pix_desc->log2_chroma_h);
             }
             for (i = 0; i < lines; i++) {
                 int j;
                 leftp  = s->input_views[LEFT]->data[plane] +
                          s->input_views[LEFT]->linesize[plane] * i;
                 rightp = s->input_views[RIGHT]->data[plane] +
                          s->input_views[RIGHT]->linesize[plane] * i;
                 dstp   = out->data[plane] + out->linesize[plane] * i;
                 for (j = 0; j < length; j++) {
                     // interpolate chroma as necessary
                     if ((s->pix_desc->log2_chroma_w ||
                          s->pix_desc->log2_chroma_h) &&
                         (plane == 1 || plane == 2)) {
                         *dstp++ = (*leftp + *rightp) / 2;
                         *dstp++ = (*leftp + *rightp) / 2;
                     } else {
                         *dstp++ = *leftp;
                         *dstp++ = *rightp;
                     }
                     leftp += 1;
                     rightp += 1;
                 }
             }
         }
     } else {
         for (i = 0; i < 2; i++) {
             const uint8_t *src[4];
             uint8_t *dst[4];
             int sub_w = s->input_views[i]->width >> s->pix_desc->log2_chroma_w;

             src[0] = s->input_views[i]->data[0];
             src[1] = s->input_views[i]->data[1];
             src[2] = s->input_views[i]->data[2];

             dst[0] = out->data[0] + i * s->input_views[i]->width;
             dst[1] = out->data[1] + i * sub_w;
             dst[2] = out->data[2] + i * sub_w;

             av_image_copy(dst, out->linesize, src, s->input_views[i]->linesize,
                           s->input_views[i]->format,
                           s->input_views[i]->width,
                           s->input_views[i]->height);
         }
     }
 }

 static void vertical_frame_pack(AVFilterLink *outlink,
                                 AVFrame *out,
                                 int interleaved)
 {
     AVFilterContext *ctx = outlink->src;
     FramepackContext *s = ctx->priv;
     int i;

     for (i = 0; i < 2; i++) {
         const uint8_t *src[4];
         uint8_t *dst[4];
         int linesizes[4];
         int sub_h = s->input_views[i]->height >> s->pix_desc->log2_chroma_h;

         src[0] = s->input_views[i]->data[0];
         src[1] = s->input_views[i]->data[1];
         src[2] = s->input_views[i]->data[2];

         dst[0] = out->data[0] + i * out->linesize[0] *
                  (interleaved + s->input_views[i]->height * (1 - interleaved));
         dst[1] = out->data[1] + i * out->linesize[1] *
                  (interleaved + sub_h * (1 - interleaved));
         dst[2] = out->data[2] + i * out->linesize[2] *
                  (interleaved + sub_h * (1 - interleaved));

         linesizes[0] = out->linesize[0] +
                        interleaved * out->linesize[0];
         linesizes[1] = out->linesize[1] +
                        interleaved * out->linesize[1];
         linesizes[2] = out->linesize[2] +
                        interleaved * out->linesize[2];

         av_image_copy(dst, linesizes, src, s->input_views[i]->linesize,
                       s->input_views[i]->format,
                       s->input_views[i]->width,
                       s->input_views[i]->height);
     }
 }

 static av_always_inline void spatial_frame_pack(AVFilterLink *outlink,
                                                 AVFrame *dst)
 {
     AVFilterContext *ctx = outlink->src;
     FramepackContext *s = ctx->priv;
     switch (s->format) {
     case AV_STEREO3D_SIDEBYSIDE:
         horizontal_frame_pack(outlink, dst, 0);
         break;
     case AV_STEREO3D_COLUMNS:
         horizontal_frame_pack(outlink, dst, 1);
         break;
     case AV_STEREO3D_TOPBOTTOM:
         vertical_frame_pack(outlink, dst, 0);
         break;
     case AV_STEREO3D_LINES:
         vertical_frame_pack(outlink, dst, 1);
         break;
     }
 }

 static int try_push_frame(AVFilterContext *ctx)
 {
     FramepackContext *s = ctx->priv;
     AVFilterLink *outlink = ctx->outputs[0];
     AVStereo3D *stereo;
     int ret, i;

     if (!(s->input_views[0] && s->input_views[1]))
         return 0;
     if (s->format == AV_STEREO3D_FRAMESEQUENCE) {
         int64_t pts = s->input_views[0]->pts;

         for (i = 0; i < 2; i++) {
             // set correct timestamps
             if (pts != AV_NOPTS_VALUE)
                 s->input_views[i]->pts = i == 0 ? pts * 2 : pts * 2 + av_rescale_q(1, av_inv_q(outlink->frame_rate), outlink->time_base);

             // set stereo3d side data
             stereo = av_stereo3d_create_side_data(s->input_views[i]);
             if (!stereo)
                 return AVERROR(ENOMEM);
             stereo->type = s->format;
             stereo->view = i == LEFT ? AV_STEREO3D_VIEW_LEFT
                                      : AV_STEREO3D_VIEW_RIGHT;

             // filter the frame and immediately relinquish its pointer
             ret = ff_filter_frame(outlink, s->input_views[i]);
             s->input_views[i] = NULL;
             if (ret < 0)
                 return ret;
         }
         return ret;
     } else {
         AVFrame *dst = ff_get_video_buffer(outlink, outlink->w, outlink->h);
         if (!dst)
             return AVERROR(ENOMEM);

         spatial_frame_pack(outlink, dst);

         // get any property from the original frame
         ret = av_frame_copy_props(dst, s->input_views[LEFT]);
         if (ret < 0) {
             av_frame_free(&dst);
             return ret;
         }

         for (i = 0; i < 2; i++)
             av_frame_free(&s->input_views[i]);

         // set stereo3d side data
         stereo = av_stereo3d_create_side_data(dst);
         if (!stereo) {
             av_frame_free(&dst);
             return AVERROR(ENOMEM);
         }
         stereo->type = s->format;

         return ff_filter_frame(outlink, dst);
     }
 }

 static int activate(AVFilterContext *ctx)
 {
     AVFilterLink *outlink = ctx->outputs[0];
     FramepackContext *s = ctx->priv;
     int ret;

     FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, ctx);

     if (!s->input_views[0]) {
         ret = ff_inlink_consume_frame(ctx->inputs[0], &s->input_views[0]);
         if (ret < 0)
             return ret;
     }

     if (!s->input_views[1]) {
         ret = ff_inlink_consume_frame(ctx->inputs[1], &s->input_views[1]);
         if (ret < 0)
             return ret;
     }

     if (s->input_views[0] && s->input_views[1])
         return try_push_frame(ctx);

     FF_FILTER_FORWARD_STATUS(ctx->inputs[0], outlink);
     FF_FILTER_FORWARD_STATUS(ctx->inputs[1], outlink);

     if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
         !ff_outlink_get_status(ctx->inputs[0]) &&
         !s->input_views[0]) {
         ff_inlink_request_frame(ctx->inputs[0]);
         return 0;
     }

     if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
         !ff_outlink_get_status(ctx->inputs[1]) &&
         !s->input_views[1]) {
         ff_inlink_request_frame(ctx->inputs[1]);
         return 0;
     }

     return FFERROR_NOT_READY;
 }

 #define OFFSET(x) offsetof(FramepackContext, x)
 #define VF AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM
 static const AVOption framepack_options[] = {
     { "format", "Frame pack output format", OFFSET(format), AV_OPT_TYPE_INT,
         { .i64 = AV_STEREO3D_SIDEBYSIDE }, 0, INT_MAX, .flags = VF, .unit = "format" },
     { "sbs", "Views are packed next to each other", 0, AV_OPT_TYPE_CONST,
         { .i64 = AV_STEREO3D_SIDEBYSIDE }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
     { "tab", "Views are packed on top of each other", 0, AV_OPT_TYPE_CONST,
         { .i64 = AV_STEREO3D_TOPBOTTOM }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
     { "frameseq", "Views are one after the other", 0, AV_OPT_TYPE_CONST,
         { .i64 = AV_STEREO3D_FRAMESEQUENCE }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
     { "lines", "Views are interleaved by lines", 0, AV_OPT_TYPE_CONST,
         { .i64 = AV_STEREO3D_LINES }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
     { "columns", "Views are interleaved by columns", 0, AV_OPT_TYPE_CONST,
         { .i64 = AV_STEREO3D_COLUMNS }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
     { NULL },
 };

 AVFILTER_DEFINE_CLASS(framepack);

 static const AVFilterPad framepack_inputs[] = {
     {
         .name         = "left",
         .type         = AVMEDIA_TYPE_VIDEO,
     },
     {
         .name         = "right",
         .type         = AVMEDIA_TYPE_VIDEO,
     },
     { NULL }
 };

 static const AVFilterPad framepack_outputs[] = {
     {
         .name          = "packed",
         .type          = AVMEDIA_TYPE_VIDEO,
         .config_props  = config_output,
     },
     { NULL }
 };

 AVFilter ff_vf_framepack = {
     .name          = "framepack",
     .description   = NULL_IF_CONFIG_SMALL("Generate a frame packed stereoscopic video."),
     .priv_size     = sizeof(FramepackContext),
     .priv_class    = &framepack_class,
     .query_formats = query_formats,
     .inputs        = framepack_inputs,
     .outputs       = framepack_outputs,
     .activate      = activate,
     .uninit        = framepack_uninit,
 };
	/*
	* Copyright (c) 2013 Vittorio Giovara
	*
	* 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
	* Generate a frame packed video, by combining two views in a single surface.
	*/

	#include <string.h>

	#include "libavutil/common.h"
	#include "libavutil/imgutils.h"
	#include "libavutil/opt.h"
	#include "libavutil/pixdesc.h"
	#include "libavutil/rational.h"
	#include "libavutil/stereo3d.h"

	#include "avfilter.h"
	#include "filters.h"
	#include "formats.h"
	#include "internal.h"
	#include "video.h"

	#define LEFT 0
	#define RIGHT 1

	typedef struct FramepackContext {
	const AVClass *class;

	const AVPixFmtDescriptor *pix_desc; ///< agreed pixel format

	enum AVStereo3DType format; ///< frame pack type output

	AVFrame *input_views[2]; ///< input frames
	} FramepackContext;

	static const enum AVPixelFormat formats_supported[] = {
	AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
	AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVJ420P,
	AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P,
	AV_PIX_FMT_NONE
	};

	static int query_formats(AVFilterContext *ctx)
	{
	// this will ensure that formats are the same on all pads
	AVFilterFormats *fmts_list = ff_make_format_list(formats_supported);
	if (!fmts_list)
	return AVERROR(ENOMEM);
	return ff_set_common_formats(ctx, fmts_list);
	}

	static av_cold void framepack_uninit(AVFilterContext *ctx)
	{
	FramepackContext *s = ctx->priv;

	// clean any leftover frame
	av_frame_free(&s->input_views[LEFT]);
	av_frame_free(&s->input_views[RIGHT]);
	}

	static int config_output(AVFilterLink *outlink)
	{
	AVFilterContext *ctx = outlink->src;
	FramepackContext *s = outlink->src->priv;

	int width = ctx->inputs[LEFT]->w;
	int height = ctx->inputs[LEFT]->h;
	AVRational time_base = ctx->inputs[LEFT]->time_base;
	AVRational frame_rate = ctx->inputs[LEFT]->frame_rate;

	// check size and fps match on the other input
	if (width != ctx->inputs[RIGHT]->w \|\|
	height != ctx->inputs[RIGHT]->h) {
	av_log(ctx, AV_LOG_ERROR,
	"Left and right sizes differ (%dx%d vs %dx%d).\n",
	width, height,
	ctx->inputs[RIGHT]->w, ctx->inputs[RIGHT]->h);
	return AVERROR_INVALIDDATA;
	} else if (av_cmp_q(time_base, ctx->inputs[RIGHT]->time_base) != 0) {
	av_log(ctx, AV_LOG_ERROR,
	"Left and right time bases differ (%d/%d vs %d/%d).\n",
	time_base.num, time_base.den,
	ctx->inputs[RIGHT]->time_base.num,
	ctx->inputs[RIGHT]->time_base.den);
	return AVERROR_INVALIDDATA;
	} else if (av_cmp_q(frame_rate, ctx->inputs[RIGHT]->frame_rate) != 0) {
	av_log(ctx, AV_LOG_ERROR,
	"Left and right framerates differ (%d/%d vs %d/%d).\n",
	frame_rate.num, frame_rate.den,
	ctx->inputs[RIGHT]->frame_rate.num,
	ctx->inputs[RIGHT]->frame_rate.den);
	return AVERROR_INVALIDDATA;
	}

	s->pix_desc = av_pix_fmt_desc_get(outlink->format);
	if (!s->pix_desc)
	return AVERROR_BUG;

	// modify output properties as needed
	switch (s->format) {
	case AV_STEREO3D_FRAMESEQUENCE:
	time_base.den *= 2;
	frame_rate.num *= 2;
	break;
	case AV_STEREO3D_COLUMNS:
	case AV_STEREO3D_SIDEBYSIDE:
	width *= 2;
	break;
	case AV_STEREO3D_LINES:
	case AV_STEREO3D_TOPBOTTOM:
	height *= 2;
	break;
	default:
	av_log(ctx, AV_LOG_ERROR, "Unknown packing mode.");
	return AVERROR_INVALIDDATA;
	}

	outlink->w = width;
	outlink->h = height;
	outlink->time_base = time_base;
	outlink->frame_rate = frame_rate;

	return 0;
	}

	static void horizontal_frame_pack(AVFilterLink *outlink,
	AVFrame *out,
	int interleaved)
	{
	AVFilterContext *ctx = outlink->src;
	FramepackContext *s = ctx->priv;
	int i, plane;

	if (interleaved) {
	const uint8_t *leftp = s->input_views[LEFT]->data[0];
	const uint8_t *rightp = s->input_views[RIGHT]->data[0];
	uint8_t *dstp = out->data[0];
	int length = out->width / 2;
	int lines = out->height;

	for (plane = 0; plane < s->pix_desc->nb_components; plane++) {
	if (plane == 1 \|\| plane == 2) {
	length = AV_CEIL_RSHIFT(out->width / 2, s->pix_desc->log2_chroma_w);
	lines = AV_CEIL_RSHIFT(out->height, s->pix_desc->log2_chroma_h);
	}
	for (i = 0; i < lines; i++) {
	int j;
	leftp = s->input_views[LEFT]->data[plane] +
	s->input_views[LEFT]->linesize[plane] * i;
	rightp = s->input_views[RIGHT]->data[plane] +
	s->input_views[RIGHT]->linesize[plane] * i;
	dstp = out->data[plane] + out->linesize[plane] * i;
	for (j = 0; j < length; j++) {
	// interpolate chroma as necessary
	if ((s->pix_desc->log2_chroma_w \|\|
	s->pix_desc->log2_chroma_h) &&
	(plane == 1 \|\| plane == 2)) {
	dstp++ = (leftp + *rightp) / 2;
	dstp++ = (leftp + *rightp) / 2;
	} else {
	dstp++ = leftp;
	dstp++ = rightp;
	}
	leftp += 1;
	rightp += 1;
	}
	}
	}
	} else {
	for (i = 0; i < 2; i++) {
	const uint8_t *src[4];
	uint8_t *dst[4];
	int sub_w = s->input_views[i]->width >> s->pix_desc->log2_chroma_w;

	src[0] = s->input_views[i]->data[0];
	src[1] = s->input_views[i]->data[1];
	src[2] = s->input_views[i]->data[2];

	dst[0] = out->data[0] + i * s->input_views[i]->width;
	dst[1] = out->data[1] + i * sub_w;
	dst[2] = out->data[2] + i * sub_w;

	av_image_copy(dst, out->linesize, src, s->input_views[i]->linesize,
	s->input_views[i]->format,
	s->input_views[i]->width,
	s->input_views[i]->height);
	}
	}
	}

	static void vertical_frame_pack(AVFilterLink *outlink,
	AVFrame *out,
	int interleaved)
	{
	AVFilterContext *ctx = outlink->src;
	FramepackContext *s = ctx->priv;
	int i;

	for (i = 0; i < 2; i++) {
	const uint8_t *src[4];
	uint8_t *dst[4];
	int linesizes[4];
	int sub_h = s->input_views[i]->height >> s->pix_desc->log2_chroma_h;

	src[0] = s->input_views[i]->data[0];
	src[1] = s->input_views[i]->data[1];
	src[2] = s->input_views[i]->data[2];

	dst[0] = out->data[0] + i * out->linesize[0] *
	(interleaved + s->input_views[i]->height * (1 - interleaved));
	dst[1] = out->data[1] + i * out->linesize[1] *
	(interleaved + sub_h * (1 - interleaved));
	dst[2] = out->data[2] + i * out->linesize[2] *
	(interleaved + sub_h * (1 - interleaved));

	linesizes[0] = out->linesize[0] +
	interleaved * out->linesize[0];
	linesizes[1] = out->linesize[1] +
	interleaved * out->linesize[1];
	linesizes[2] = out->linesize[2] +
	interleaved * out->linesize[2];

	av_image_copy(dst, linesizes, src, s->input_views[i]->linesize,
	s->input_views[i]->format,
	s->input_views[i]->width,
	s->input_views[i]->height);
	}
	}

	static av_always_inline void spatial_frame_pack(AVFilterLink *outlink,
	AVFrame *dst)
	{
	AVFilterContext *ctx = outlink->src;
	FramepackContext *s = ctx->priv;
	switch (s->format) {
	case AV_STEREO3D_SIDEBYSIDE:
	horizontal_frame_pack(outlink, dst, 0);
	break;
	case AV_STEREO3D_COLUMNS:
	horizontal_frame_pack(outlink, dst, 1);
	break;
	case AV_STEREO3D_TOPBOTTOM:
	vertical_frame_pack(outlink, dst, 0);
	break;
	case AV_STEREO3D_LINES:
	vertical_frame_pack(outlink, dst, 1);
	break;
	}
	}

	static int try_push_frame(AVFilterContext *ctx)
	{
	FramepackContext *s = ctx->priv;
	AVFilterLink *outlink = ctx->outputs[0];
	AVStereo3D *stereo;
	int ret, i;

	if (!(s->input_views[0] && s->input_views[1]))
	return 0;
	if (s->format == AV_STEREO3D_FRAMESEQUENCE) {
	int64_t pts = s->input_views[0]->pts;

	for (i = 0; i < 2; i++) {
	// set correct timestamps
	if (pts != AV_NOPTS_VALUE)
	s->input_views[i]->pts = i == 0 ? pts * 2 : pts * 2 + av_rescale_q(1, av_inv_q(outlink->frame_rate), outlink->time_base);

	// set stereo3d side data
	stereo = av_stereo3d_create_side_data(s->input_views[i]);
	if (!stereo)
	return AVERROR(ENOMEM);
	stereo->type = s->format;
	stereo->view = i == LEFT ? AV_STEREO3D_VIEW_LEFT
	: AV_STEREO3D_VIEW_RIGHT;

	// filter the frame and immediately relinquish its pointer
	ret = ff_filter_frame(outlink, s->input_views[i]);
	s->input_views[i] = NULL;
	if (ret < 0)
	return ret;
	}
	return ret;
	} else {
	AVFrame *dst = ff_get_video_buffer(outlink, outlink->w, outlink->h);
	if (!dst)
	return AVERROR(ENOMEM);

	spatial_frame_pack(outlink, dst);

	// get any property from the original frame
	ret = av_frame_copy_props(dst, s->input_views[LEFT]);
	if (ret < 0) {
	av_frame_free(&dst);
	return ret;
	}

	for (i = 0; i < 2; i++)
	av_frame_free(&s->input_views[i]);

	// set stereo3d side data
	stereo = av_stereo3d_create_side_data(dst);
	if (!stereo) {
	av_frame_free(&dst);
	return AVERROR(ENOMEM);
	}
	stereo->type = s->format;

	return ff_filter_frame(outlink, dst);
	}
	}

	static int activate(AVFilterContext *ctx)
	{
	AVFilterLink *outlink = ctx->outputs[0];
	FramepackContext *s = ctx->priv;
	int ret;

	FF_FILTER_FORWARD_STATUS_BACK_ALL(outlink, ctx);

	if (!s->input_views[0]) {
	ret = ff_inlink_consume_frame(ctx->inputs[0], &s->input_views[0]);
	if (ret < 0)
	return ret;
	}

	if (!s->input_views[1]) {
	ret = ff_inlink_consume_frame(ctx->inputs[1], &s->input_views[1]);
	if (ret < 0)
	return ret;
	}

	if (s->input_views[0] && s->input_views[1])
	return try_push_frame(ctx);

	FF_FILTER_FORWARD_STATUS(ctx->inputs[0], outlink);
	FF_FILTER_FORWARD_STATUS(ctx->inputs[1], outlink);

	if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
	!ff_outlink_get_status(ctx->inputs[0]) &&
	!s->input_views[0]) {
	ff_inlink_request_frame(ctx->inputs[0]);
	return 0;
	}

	if (ff_outlink_frame_wanted(ctx->outputs[0]) &&
	!ff_outlink_get_status(ctx->inputs[1]) &&
	!s->input_views[1]) {
	ff_inlink_request_frame(ctx->inputs[1]);
	return 0;
	}

	return FFERROR_NOT_READY;
	}

	#define OFFSET(x) offsetof(FramepackContext, x)
	#define VF AV_OPT_FLAG_VIDEO_PARAM \| AV_OPT_FLAG_FILTERING_PARAM
	static const AVOption framepack_options[] = {
	{ "format", "Frame pack output format", OFFSET(format), AV_OPT_TYPE_INT,
	{ .i64 = AV_STEREO3D_SIDEBYSIDE }, 0, INT_MAX, .flags = VF, .unit = "format" },
	{ "sbs", "Views are packed next to each other", 0, AV_OPT_TYPE_CONST,
	{ .i64 = AV_STEREO3D_SIDEBYSIDE }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
	{ "tab", "Views are packed on top of each other", 0, AV_OPT_TYPE_CONST,
	{ .i64 = AV_STEREO3D_TOPBOTTOM }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
	{ "frameseq", "Views are one after the other", 0, AV_OPT_TYPE_CONST,
	{ .i64 = AV_STEREO3D_FRAMESEQUENCE }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
	{ "lines", "Views are interleaved by lines", 0, AV_OPT_TYPE_CONST,
	{ .i64 = AV_STEREO3D_LINES }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
	{ "columns", "Views are interleaved by columns", 0, AV_OPT_TYPE_CONST,
	{ .i64 = AV_STEREO3D_COLUMNS }, INT_MIN, INT_MAX, .flags = VF, .unit = "format" },
	{ NULL },
	};

	AVFILTER_DEFINE_CLASS(framepack);

	static const AVFilterPad framepack_inputs[] = {
	{
	.name = "left",
	.type = AVMEDIA_TYPE_VIDEO,
	},
	{
	.name = "right",
	.type = AVMEDIA_TYPE_VIDEO,
	},
	{ NULL }
	};

	static const AVFilterPad framepack_outputs[] = {
	{
	.name = "packed",
	.type = AVMEDIA_TYPE_VIDEO,
	.config_props = config_output,
	},
	{ NULL }
	};

	AVFilter ff_vf_framepack = {
	.name = "framepack",
	.description = NULL_IF_CONFIG_SMALL("Generate a frame packed stereoscopic video."),
	.priv_size = sizeof(FramepackContext),
	.priv_class = &framepack_class,
	.query_formats = query_formats,
	.inputs = framepack_inputs,
	.outputs = framepack_outputs,
	.activate = activate,
	.uninit = framepack_uninit,
	};