[FFmpeg-devel] [PATCH] lavfi: add colorkey_opencl filter
Jarek Samic
cldfire3 at gmail.com
Wed Apr 10 06:37:20 EEST 2019
This is a direct port of the CPU filter.
Signed-off-by: Jarek Samic <cldfire3 at gmail.com>
---
This is my submission for the GSoC OpenCL video filters project qualification task.
Command you can use to try it out:
./ffmpeg -i some_video -i some_img -init_hw_device opencl=gpu -filter_hw_device gpu -filter_complex "[0:v]format=rgba, hwupload, colorkey_opencl=yellow:0.4:0.2, hwdownload, format=rgba[over];[1:v][over]overlay" output
Based on simple observation of that command running vs. an equivalent one with the CPU
colorkey filter, it would appear that the OpenCL version is ~10-20% faster including
the overhead to upload / download from the GPU (at least with my test input and
hardware).
You will notice that I am using overlay rather than overlay_opencl above. I am not
sure what's going on, but the overlay_opencl filter is not working for me: every time
I try to use it it either stops after the first couple of frames or spits out
duplicate frames forever. Even just running this command that is basically a copy of
the example command to overlay an image logo on the top-left corner of an input video:
./ffmpeg -i ../video.mp4 -i ../img.png -init_hw_device opencl=gpu -filter_hw_device gpu -filter_complex "[0:v]hwupload[a], [1:v]format=yuv420p, hwupload[b], [a][b]overlay_opencl, hwdownload, format=yuv420p" ../vid_test.mp4
Results in an infinite number of duplicate frames. (The format of the input video is
yuv420p, to be clear.)
Before I take the time to dig in and investigate what's going on, is anyone else
aware of what could be causing this (or any existing known issues)?
configure | 1 +
doc/filters.texi | 33 +++++
libavfilter/Makefile | 2 +
libavfilter/allfilters.c | 1 +
libavfilter/opencl/colorkey.cl | 45 ++++++
libavfilter/opencl_source.h | 1 +
libavfilter/vf_colorkey_opencl.c | 234 +++++++++++++++++++++++++++++++
7 files changed, 317 insertions(+)
create mode 100644 libavfilter/opencl/colorkey.cl
create mode 100644 libavfilter/vf_colorkey_opencl.c
diff --git a/configure b/configure
index f6123f53e5..a4dd9ee167 100755
--- a/configure
+++ b/configure
@@ -3410,6 +3410,7 @@ boxblur_filter_deps="gpl"
boxblur_opencl_filter_deps="opencl gpl"
bs2b_filter_deps="libbs2b"
colormatrix_filter_deps="gpl"
+colorkey_opencl_filter_deps="opencl"
convolution_opencl_filter_deps="opencl"
convolve_filter_deps="avcodec"
convolve_filter_select="fft"
diff --git a/doc/filters.texi b/doc/filters.texi
index 867607d870..390c8b97cf 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -19030,6 +19030,39 @@ Apply erosion filter with threshold0 set to 30, threshold1 set 40, threshold2 se
@end example
@end itemize
+ at section colorkey_opencl
+RGB colorspace color keying.
+
+The filter accepts the following options:
+
+ at table @option
+ at item color
+The color which will be replaced with transparency.
+
+ at item similarity
+Similarity percentage with the key color.
+
+0.01 matches only the exact key color, while 1.0 matches everything.
+
+ at item blend
+Blend percentage.
+
+0.0 makes pixels either fully transparent, or not transparent at all.
+
+Higher values result in semi-transparent pixels, with a higher transparency
+the more similar the pixels color is to the key color.
+ at end table
+
+ at subsection Examples
+
+ at itemize
+ at item
+Make every semi-green pixel in the input transparent with some slight blending:
+ at example
+-i INPUT -vf "hwupload, colorkey_opencl=green:0.3:0.1, hwdownload" OUTPUT
+ at end example
+ at end itemize
+
@section overlay_opencl
Overlay one video on top of another.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index fef6ec5c55..9589dd8747 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -176,6 +176,8 @@ OBJS-$(CONFIG_CODECVIEW_FILTER) += vf_codecview.o
OBJS-$(CONFIG_COLORBALANCE_FILTER) += vf_colorbalance.o
OBJS-$(CONFIG_COLORCHANNELMIXER_FILTER) += vf_colorchannelmixer.o
OBJS-$(CONFIG_COLORKEY_FILTER) += vf_colorkey.o
+OBJS-$(CONFIG_COLORKEY_OPENCL_FILTER) += vf_colorkey_opencl.o opencl.o \
+ opencl/colorkey.o
OBJS-$(CONFIG_COLORLEVELS_FILTER) += vf_colorlevels.o
OBJS-$(CONFIG_COLORMATRIX_FILTER) += vf_colormatrix.o
OBJS-$(CONFIG_COLORSPACE_FILTER) += vf_colorspace.o colorspace.o colorspacedsp.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index c51ae0f3c7..ff4eb5bf6b 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -165,6 +165,7 @@ extern AVFilter ff_vf_codecview;
extern AVFilter ff_vf_colorbalance;
extern AVFilter ff_vf_colorchannelmixer;
extern AVFilter ff_vf_colorkey;
+extern AVFilter ff_vf_colorkey_opencl;
extern AVFilter ff_vf_colorlevels;
extern AVFilter ff_vf_colormatrix;
extern AVFilter ff_vf_colorspace;
diff --git a/libavfilter/opencl/colorkey.cl b/libavfilter/opencl/colorkey.cl
new file mode 100644
index 0000000000..5d8a0bb8df
--- /dev/null
+++ b/libavfilter/opencl/colorkey.cl
@@ -0,0 +1,45 @@
+/*
+ * 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
+ */
+
+__kernel void colorkey(
+ __read_only image2d_t src,
+ __write_only image2d_t dst,
+ uchar4 colorkey_rgba,
+ float similarity,
+ float blend
+) {
+ const sampler_t sampler = CLK_NORMALIZED_COORDS_FALSE |
+ CLK_FILTER_NEAREST;
+ int2 loc = (int2)(get_global_id(0), get_global_id(1));
+ float4 pixel = read_imagef(src, sampler, loc);
+
+ float dr = pixel.s0 - (float)colorkey_rgba.s0 / 255.0;
+ float dg = pixel.s1 - (float)colorkey_rgba.s1 / 255.0;
+ float db = pixel.s2 - (float)colorkey_rgba.s2 / 255.0;
+
+ double diff = sqrt(dr * dr + dg * dg + db * db);
+
+ if (blend > 0.0001) {
+ pixel.s3 = clamp((diff - similarity) / blend, 0.0, 1.0);
+ } else {
+ pixel.s3 = (diff > similarity) ? 1.0 : 0.0;
+ }
+
+ write_imagef(dst, loc, pixel);
+}
+
diff --git a/libavfilter/opencl_source.h b/libavfilter/opencl_source.h
index 4118138c30..51f7178cf2 100644
--- a/libavfilter/opencl_source.h
+++ b/libavfilter/opencl_source.h
@@ -20,6 +20,7 @@
#define AVFILTER_OPENCL_SOURCE_H
extern const char *ff_opencl_source_avgblur;
+extern const char *ff_opencl_source_colorkey;
extern const char *ff_opencl_source_colorspace_common;
extern const char *ff_opencl_source_convolution;
extern const char *ff_opencl_source_neighbor;
diff --git a/libavfilter/vf_colorkey_opencl.c b/libavfilter/vf_colorkey_opencl.c
new file mode 100644
index 0000000000..4769c529b0
--- /dev/null
+++ b/libavfilter/vf_colorkey_opencl.c
@@ -0,0 +1,234 @@
+/*
+ * 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
+ cl_uchar4 colorkey_rgba[4];
+ // 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);
+
+ ctx->kernel_colorkey = clCreateKernel(ctx->ocf.program, "colorkey", &cle);
+ CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create horizontal "
+ "kernel %d.\n", cle);
+
+ 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 &&
+ fmt != AV_PIX_FMT_NONE
+ ) {
+ 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_uchar4, &colorkey_ctx->colorkey_rgba);
+ CL_SET_KERNEL_ARG(colorkey_ctx->kernel_colorkey, 3, float, &colorkey_ctx->similarity);
+ 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
+};
+
--
2.21.0
More information about the ffmpeg-devel
mailing list