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

 /*
  * 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 "libavutil/opt.h"
 #include "libavutil/imgutils.h"
 #include "avfilter.h"
 #include "formats.h"
 #include "internal.h"
 #include "opencl.h"
 #include "opencl_source.h"
 #include "video.h"

 typedef struct ColorkeyOpenCLContext {
     OpenCLFilterContext ocf;
     // Whether or not the above `OpenCLFilterContext` has been initialized
     int initialized;

     cl_command_queue command_queue;
     cl_kernel kernel_colorkey;

     // The color we are supposed to replace with transparency
     uint8_t colorkey_rgba[4];
     // Stored as a normalized float for passing to the OpenCL kernel
     cl_float4 colorkey_rgba_float;
     // Similarity percentage compared to `colorkey_rgba`, ranging from `0.01` to `1.0`
     // where `0.01` matches only the key color and `1.0` matches all colors
     float similarity;
     // Blending percentage where `0.0` results in fully transparent pixels, `1.0` results
     // in fully opaque pixels, and numbers in between result in transparency that varies
     // based on the similarity to the key color
     float blend;
 } ColorkeyOpenCLContext;

 static int colorkey_opencl_init(AVFilterContext *avctx)
 {
     ColorkeyOpenCLContext *ctx = avctx->priv;
     cl_int cle;
     int err;

     err = ff_opencl_filter_load_program(avctx, &ff_opencl_source_colorkey, 1);
     if (err < 0)
         goto fail;

     ctx->command_queue = clCreateCommandQueue(
         ctx->ocf.hwctx->context,
         ctx->ocf.hwctx->device_id,
         0,
         &cle
     );

     CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create OpenCL command queue %d.\n", cle);

     if (ctx->blend > 0.0001) {
         ctx->kernel_colorkey = clCreateKernel(ctx->ocf.program, "colorkey_blend", &cle);
         CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create colorkey_blend kernel: %d.\n", cle);
     } else {
         ctx->kernel_colorkey = clCreateKernel(ctx->ocf.program, "colorkey", &cle);
         CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create colorkey kernel: %d.\n", cle);
     }

     for (int i = 0; i < 4; ++i) {
         ctx->colorkey_rgba_float.s[i] = (float)ctx->colorkey_rgba[i] / 255.0;
     }

     ctx->initialized = 1;
     return 0;

 fail:
     if (ctx->command_queue)
         clReleaseCommandQueue(ctx->command_queue);
     if (ctx->kernel_colorkey)
         clReleaseKernel(ctx->kernel_colorkey);
     return err;
 }

 static int filter_frame(AVFilterLink *link, AVFrame *input_frame)
 {
     AVFilterContext *avctx = link->dst;
     AVFilterLink *outlink = avctx->outputs[0];
     ColorkeyOpenCLContext *colorkey_ctx = avctx->priv;
     AVFrame *output_frame = NULL;
     int err;
     cl_int cle;
     size_t global_work[2];
     cl_mem src, dst;

     if (!input_frame->hw_frames_ctx)
         return AVERROR(EINVAL);

     if (!colorkey_ctx->initialized) {
         AVHWFramesContext *input_frames_ctx =
             (AVHWFramesContext*)input_frame->hw_frames_ctx->data;
         int fmt = input_frames_ctx->sw_format;

         // Make sure the input is a format we support
         if (fmt != AV_PIX_FMT_ARGB &&
             fmt != AV_PIX_FMT_RGBA &&
             fmt != AV_PIX_FMT_ABGR &&
             fmt != AV_PIX_FMT_BGRA
         ) {
             av_log(avctx, AV_LOG_ERROR, "unsupported (non-RGB) format in colorkey_opencl.\n");
             err = AVERROR(ENOSYS);
             goto fail;
         }

         err = colorkey_opencl_init(avctx);
         if (err < 0)
             goto fail;
     }

     // This filter only operates on RGB data and we know that will be on the first plane
     src = (cl_mem)input_frame->data[0];
     output_frame = ff_get_video_buffer(outlink, outlink->w, outlink->h);
     if (!output_frame) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
     dst = (cl_mem)output_frame->data[0];

     CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 0, cl_mem, &src);
     CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 1, cl_mem, &dst);
     CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 2, cl_float4, &colorkey_ctx->colorkey_rgba_float);
     CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 3, float, &colorkey_ctx->similarity);
     if (colorkey_ctx->blend > 0.0001) {
         CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 4, float, &colorkey_ctx->blend);
     }

     err = ff_opencl_filter_work_size_from_image(avctx, global_work, input_frame, 0, 0);
     if (err < 0)
         goto fail;

     cle = clEnqueueNDRangeKernel(
         colorkey_ctx->command_queue,
         colorkey_ctx->kernel_colorkey,
         2,
         NULL,
         global_work,
         NULL,
         0,
         NULL,
         NULL
     );

     CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to enqueue colorkey kernel: %d.\n", cle);

     // Run queued kernel
     cle = clFinish(colorkey_ctx->command_queue);
     CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to finish command queue: %d.\n", cle);

     err = av_frame_copy_props(output_frame, input_frame);
     if (err < 0)
         goto fail;

     av_frame_free(&input_frame);

     return ff_filter_frame(outlink, output_frame);

 fail:
     clFinish(colorkey_ctx->command_queue);
     av_frame_free(&input_frame);
     av_frame_free(&output_frame);
     return err;
 }

 static av_cold void colorkey_opencl_uninit(AVFilterContext *avctx)
 {
     ColorkeyOpenCLContext *ctx = avctx->priv;
     cl_int cle;

     if (ctx->kernel_colorkey) {
         cle = clReleaseKernel(ctx->kernel_colorkey);
         if (cle != CL_SUCCESS)
             av_log(avctx, AV_LOG_ERROR, "Failed to release "
                    "kernel: %d.\n", cle);
     }

     if (ctx->command_queue) {
         cle = clReleaseCommandQueue(ctx->command_queue);
         if (cle != CL_SUCCESS)
             av_log(avctx, AV_LOG_ERROR, "Failed to release "
                    "command queue: %d.\n", cle);
     }

     ff_opencl_filter_uninit(avctx);
 }

 static const AVFilterPad colorkey_opencl_inputs[] = {
     {
         .name = "default",
         .type = AVMEDIA_TYPE_VIDEO,
         .filter_frame = filter_frame,
         .config_props = &ff_opencl_filter_config_input,
     },
     { NULL }
 };

 static const AVFilterPad colorkey_opencl_outputs[] = {
     {
         .name = "default",
         .type = AVMEDIA_TYPE_VIDEO,
         .config_props = &ff_opencl_filter_config_output,
     },
     { NULL }
 };

 #define OFFSET(x) offsetof(ColorkeyOpenCLContext, x)
 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM

 static const AVOption colorkey_opencl_options[] = {
     { "color", "set the colorkey key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
     { "similarity", "set the colorkey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
     { "blend", "set the colorkey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
     { NULL }
 };

 AVFILTER_DEFINE_CLASS(colorkey_opencl);

 AVFilter ff_vf_colorkey_opencl = {
     .name           = "colorkey_opencl",
     .description    = NULL_IF_CONFIG_SMALL("Turns a certain color into transparency. Operates on RGB colors."),
     .priv_size      = sizeof(ColorkeyOpenCLContext),
     .priv_class     = &colorkey_opencl_class,
     .init           = &ff_opencl_filter_init,
     .uninit         = &colorkey_opencl_uninit,
     .query_formats  = &ff_opencl_filter_query_formats,
     .inputs         = colorkey_opencl_inputs,
     .outputs        = colorkey_opencl_outputs,
     .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE
 };
	/*
	* 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 "libavutil/opt.h"
	#include "libavutil/imgutils.h"
	#include "avfilter.h"
	#include "formats.h"
	#include "internal.h"
	#include "opencl.h"
	#include "opencl_source.h"
	#include "video.h"

	typedef struct ColorkeyOpenCLContext {
	OpenCLFilterContext ocf;
	// Whether or not the above `OpenCLFilterContext` has been initialized
	int initialized;

	cl_command_queue command_queue;
	cl_kernel kernel_colorkey;

	// The color we are supposed to replace with transparency
	uint8_t colorkey_rgba[4];
	// Stored as a normalized float for passing to the OpenCL kernel
	cl_float4 colorkey_rgba_float;
	// Similarity percentage compared to `colorkey_rgba`, ranging from `0.01` to `1.0`
	// where `0.01` matches only the key color and `1.0` matches all colors
	float similarity;
	// Blending percentage where `0.0` results in fully transparent pixels, `1.0` results
	// in fully opaque pixels, and numbers in between result in transparency that varies
	// based on the similarity to the key color
	float blend;
	} ColorkeyOpenCLContext;

	static int colorkey_opencl_init(AVFilterContext *avctx)
	{
	ColorkeyOpenCLContext *ctx = avctx->priv;
	cl_int cle;
	int err;

	err = ff_opencl_filter_load_program(avctx, &ff_opencl_source_colorkey, 1);
	if (err < 0)
	goto fail;

	ctx->command_queue = clCreateCommandQueue(
	ctx->ocf.hwctx->context,
	ctx->ocf.hwctx->device_id,
	0,
	&cle
	);

	CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create OpenCL command queue %d.\n", cle);

	if (ctx->blend > 0.0001) {
	ctx->kernel_colorkey = clCreateKernel(ctx->ocf.program, "colorkey_blend", &cle);
	CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create colorkey_blend kernel: %d.\n", cle);
	} else {
	ctx->kernel_colorkey = clCreateKernel(ctx->ocf.program, "colorkey", &cle);
	CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create colorkey kernel: %d.\n", cle);
	}

	for (int i = 0; i < 4; ++i) {
	ctx->colorkey_rgba_float.s[i] = (float)ctx->colorkey_rgba[i] / 255.0;
	}

	ctx->initialized = 1;
	return 0;

	fail:
	if (ctx->command_queue)
	clReleaseCommandQueue(ctx->command_queue);
	if (ctx->kernel_colorkey)
	clReleaseKernel(ctx->kernel_colorkey);
	return err;
	}

	static int filter_frame(AVFilterLink link, AVFrame input_frame)
	{
	AVFilterContext *avctx = link->dst;
	AVFilterLink *outlink = avctx->outputs[0];
	ColorkeyOpenCLContext *colorkey_ctx = avctx->priv;
	AVFrame *output_frame = NULL;
	int err;
	cl_int cle;
	size_t global_work[2];
	cl_mem src, dst;

	if (!input_frame->hw_frames_ctx)
	return AVERROR(EINVAL);

	if (!colorkey_ctx->initialized) {
	AVHWFramesContext *input_frames_ctx =
	(AVHWFramesContext*)input_frame->hw_frames_ctx->data;
	int fmt = input_frames_ctx->sw_format;

	// Make sure the input is a format we support
	if (fmt != AV_PIX_FMT_ARGB &&
	fmt != AV_PIX_FMT_RGBA &&
	fmt != AV_PIX_FMT_ABGR &&
	fmt != AV_PIX_FMT_BGRA
	) {
	av_log(avctx, AV_LOG_ERROR, "unsupported (non-RGB) format in colorkey_opencl.\n");
	err = AVERROR(ENOSYS);
	goto fail;
	}

	err = colorkey_opencl_init(avctx);
	if (err < 0)
	goto fail;
	}

	// This filter only operates on RGB data and we know that will be on the first plane
	src = (cl_mem)input_frame->data[0];
	output_frame = ff_get_video_buffer(outlink, outlink->w, outlink->h);
	if (!output_frame) {
	err = AVERROR(ENOMEM);
	goto fail;
	}
	dst = (cl_mem)output_frame->data[0];

	CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 0, cl_mem, &src);
	CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 1, cl_mem, &dst);
	CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 2, cl_float4, &colorkey_ctx->colorkey_rgba_float);
	CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 3, float, &colorkey_ctx->similarity);
	if (colorkey_ctx->blend > 0.0001) {
	CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 4, float, &colorkey_ctx->blend);
	}

	err = ff_opencl_filter_work_size_from_image(avctx, global_work, input_frame, 0, 0);
	if (err < 0)
	goto fail;

	cle = clEnqueueNDRangeKernel(
	colorkey_ctx->command_queue,
	colorkey_ctx->kernel_colorkey,
	2,
	NULL,
	global_work,
	NULL,
	0,
	NULL,
	NULL
	);

	CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to enqueue colorkey kernel: %d.\n", cle);

	// Run queued kernel
	cle = clFinish(colorkey_ctx->command_queue);
	CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to finish command queue: %d.\n", cle);

	err = av_frame_copy_props(output_frame, input_frame);
	if (err < 0)
	goto fail;

	av_frame_free(&input_frame);

	return ff_filter_frame(outlink, output_frame);

	fail:
	clFinish(colorkey_ctx->command_queue);
	av_frame_free(&input_frame);
	av_frame_free(&output_frame);
	return err;
	}

	static av_cold void colorkey_opencl_uninit(AVFilterContext *avctx)
	{
	ColorkeyOpenCLContext *ctx = avctx->priv;
	cl_int cle;

	if (ctx->kernel_colorkey) {
	cle = clReleaseKernel(ctx->kernel_colorkey);
	if (cle != CL_SUCCESS)
	av_log(avctx, AV_LOG_ERROR, "Failed to release "
	"kernel: %d.\n", cle);
	}

	if (ctx->command_queue) {
	cle = clReleaseCommandQueue(ctx->command_queue);
	if (cle != CL_SUCCESS)
	av_log(avctx, AV_LOG_ERROR, "Failed to release "
	"command queue: %d.\n", cle);
	}

	ff_opencl_filter_uninit(avctx);
	}

	static const AVFilterPad colorkey_opencl_inputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.filter_frame = filter_frame,
	.config_props = &ff_opencl_filter_config_input,
	},
	{ NULL }
	};

	static const AVFilterPad colorkey_opencl_outputs[] = {
	{
	.name = "default",
	.type = AVMEDIA_TYPE_VIDEO,
	.config_props = &ff_opencl_filter_config_output,
	},
	{ NULL }
	};

	#define OFFSET(x) offsetof(ColorkeyOpenCLContext, x)
	#define FLAGS AV_OPT_FLAG_FILTERING_PARAM\|AV_OPT_FLAG_VIDEO_PARAM

	static const AVOption colorkey_opencl_options[] = {
	{ "color", "set the colorkey key color", OFFSET(colorkey_rgba), AV_OPT_TYPE_COLOR, { .str = "black" }, CHAR_MIN, CHAR_MAX, FLAGS },
	{ "similarity", "set the colorkey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, { .dbl = 0.01 }, 0.01, 1.0, FLAGS },
	{ "blend", "set the colorkey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, { .dbl = 0.0 }, 0.0, 1.0, FLAGS },
	{ NULL }
	};

	AVFILTER_DEFINE_CLASS(colorkey_opencl);

	AVFilter ff_vf_colorkey_opencl = {
	.name = "colorkey_opencl",
	.description = NULL_IF_CONFIG_SMALL("Turns a certain color into transparency. Operates on RGB colors."),
	.priv_size = sizeof(ColorkeyOpenCLContext),
	.priv_class = &colorkey_opencl_class,
	.init = &ff_opencl_filter_init,
	.uninit = &colorkey_opencl_uninit,
	.query_formats = &ff_opencl_filter_query_formats,
	.inputs = colorkey_opencl_inputs,
	.outputs = colorkey_opencl_outputs,
	.flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE
	};