[FFmpeg-devel] [PATCH v2] Chromakey CUDA
mohamed Elhadidy
mohamedpower_50 at hotmail.com
Tue Jul 5 18:16:51 EEST 2022
From: Mohamed Khaled Mohamed <56936494+MohamedElhadidy0019 at users.noreply.github.com>
V2 ChromeKey CUDA
Added Chromakey CUDA filter
v2 some changes for coding conventions
GSoC'22
Added CUDA chromakeyfilter
libavfilter/vf_chromakey_cuda.cu:the CUDA kernel for the filter
libavfilter/vf_chromakey_cuda.c: the C side that calls the kernel and gets user input
libavfilter/allfilters.c: added the filter to it
libavfilter/Makefile: added the filter to it
cuda/cuda_runtime.h: added two math CUDA functions that are used in the filter
---
compat/cuda/cuda_runtime.h | 2 +
libavfilter/Makefile | 2 +
libavfilter/allfilters.c | 1 +
libavfilter/vf_chromakey_cuda.c | 450 +++++++++++++++++++++++++++++++
libavfilter/vf_chromakey_cuda.cu | 164 +++++++++++
5 files changed, 619 insertions(+)
create mode 100644 libavfilter/vf_chromakey_cuda.c
create mode 100644 libavfilter/vf_chromakey_cuda.cu
diff --git a/compat/cuda/cuda_runtime.h b/compat/cuda/cuda_runtime.h
index 30cd085e48..5837c1ad37 100644
--- a/compat/cuda/cuda_runtime.h
+++ b/compat/cuda/cuda_runtime.h
@@ -181,7 +181,9 @@ static inline __device__ double trunc(double a) { return __builtin_trunc(a); }
static inline __device__ float fabsf(float a) { return __builtin_fabsf(a); }
static inline __device__ float fabs(float a) { return __builtin_fabsf(a); }
static inline __device__ double fabs(double a) { return __builtin_fabs(a); }
+static inline __device__ float sqrtf(float a) { return __builtin_sqrtf(a); }
+static inline __device__ float __saturatef(float a) { return __nvvm_saturate_f(a); }
static inline __device__ float __sinf(float a) { return __nvvm_sin_approx_f(a); }
static inline __device__ float __cosf(float a) { return __nvvm_cos_approx_f(a); }
static inline __device__ float __expf(float a) { return __nvvm_ex2_approx_f(a * (float)__builtin_log2(__builtin_exp(1))); }
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 22b0a0ca15..f02571c710 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -210,6 +210,8 @@ OBJS-$(CONFIG_CAS_FILTER) += vf_cas.o
OBJS-$(CONFIG_CHROMABER_VULKAN_FILTER) += vf_chromaber_vulkan.o vulkan.o vulkan_filter.o
OBJS-$(CONFIG_CHROMAHOLD_FILTER) += vf_chromakey.o
OBJS-$(CONFIG_CHROMAKEY_FILTER) += vf_chromakey.o
+OBJS-$(CONFIG_CHROMAKEY_CUDA_FILTER) += vf_chromakey_cuda.o vf_chromakey_cuda.ptx.o
+
OBJS-$(CONFIG_CHROMANR_FILTER) += vf_chromanr.o
OBJS-$(CONFIG_CHROMASHIFT_FILTER) += vf_chromashift.o
OBJS-$(CONFIG_CIESCOPE_FILTER) += vf_ciescope.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index ec70feef11..da1a96b23c 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -195,6 +195,7 @@ extern const AVFilter ff_vf_cas;
extern const AVFilter ff_vf_chromaber_vulkan;
extern const AVFilter ff_vf_chromahold;
extern const AVFilter ff_vf_chromakey;
+extern const AVFilter ff_vf_chromakey_cuda;
extern const AVFilter ff_vf_chromanr;
extern const AVFilter ff_vf_chromashift;
extern const AVFilter ff_vf_ciescope;
diff --git a/libavfilter/vf_chromakey_cuda.c b/libavfilter/vf_chromakey_cuda.c
new file mode 100644
index 0000000000..b3b037d43a
--- /dev/null
+++ b/libavfilter/vf_chromakey_cuda.c
@@ -0,0 +1,450 @@
+/*
+ * Copyright (c) 2022 Mohamed Khaled <Mohamed_Khaled_Kamal at outlook.com>
+ *
+ * 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 <float.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "libavutil/avstring.h"
+#include "libavutil/common.h"
+#include "libavutil/hwcontext.h"
+#include "libavutil/hwcontext_cuda_internal.h"
+#include "libavutil/cuda_check.h"
+#include "libavutil/internal.h"
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+#include "cuda/load_helper.h"
+
+#define FIXNUM(x) lrint((x) * (1 << 10))
+#define RGB_TO_U(rgb) (((-FIXNUM(0.16874) * rgb[0] - FIXNUM(0.33126) * rgb[1] + FIXNUM(0.50000) * rgb[2] + (1 << 9) - 1) >> 10) + 128)
+#define RGB_TO_V(rgb) (((FIXNUM(0.50000) * rgb[0] - FIXNUM(0.41869) * rgb[1] - FIXNUM(0.08131) * rgb[2] + (1 << 9) - 1) >> 10) + 128)
+
+static const enum AVPixelFormat supported_formats[] = {
+ AV_PIX_FMT_YUV420P,
+ AV_PIX_FMT_NV12,
+ AV_PIX_FMT_YUVA420P
+};
+
+#define DIV_UP(a, b) (((a) + (b)-1) / (b))
+#define BLOCKX 32
+#define BLOCKY 16
+#define CHECK_CU(x) FF_CUDA_CHECK_DL(ctx, s->hwctx->internal->cuda_dl, x)
+
+typedef struct ChromakeyCUDAContext
+{
+ const AVClass *class;
+ AVCUDADeviceContext *hwctx;
+ enum AVPixelFormat in_fmt, out_fmt;
+ const AVPixFmtDescriptor *in_desc, *out_desc;
+ int in_planes, out_planes;
+ int in_plane_depths[4];
+ int in_plane_channels[4];
+ uint8_t chromakey_rgba[4];
+ uint16_t chromakey_uv[2];
+ int is_yuv;
+ float similarity;
+ float blend;
+ AVBufferRef *frames_ctx;
+ AVFrame *frame;
+ AVFrame *tmp_frame;
+ char *w_expr;
+ char *h_expr;
+ CUcontext cu_ctx;
+ CUmodule cu_module;
+ CUfunction cu_func;
+ CUfunction cu_func_uv;
+ CUstream cu_stream;
+} ChromakeyCUDAContext;
+
+static av_cold int cudachromakey_init(AVFilterContext *ctx)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ s->frame = av_frame_alloc();
+ if (!s->frame)
+ return AVERROR(ENOMEM);
+ s->tmp_frame = av_frame_alloc();
+ if (!s->tmp_frame)
+ return AVERROR(ENOMEM);
+ return 0;
+}
+
+static av_cold void cudachromakey_uninit(AVFilterContext *ctx)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ if (s->hwctx && s->cu_module)
+ {
+ CudaFunctions *cu = s->hwctx->internal->cuda_dl;
+ CUcontext context;
+ CHECK_CU(cu->cuCtxPushCurrent(s->hwctx->cuda_ctx));
+ CHECK_CU(cu->cuModuleUnload(s->cu_module));
+ s->cu_module = NULL;
+ CHECK_CU(cu->cuCtxPopCurrent(&context));
+ }
+ av_frame_free(&s->frame);
+ av_buffer_unref(&s->frames_ctx);
+ av_frame_free(&s->tmp_frame);
+}
+
+static av_cold int init_hwframe_ctx(ChromakeyCUDAContext *s, AVBufferRef *device_ctx, int width, int height)
+{
+ AVBufferRef *out_ref = NULL;
+ AVHWFramesContext *out_ctx;
+ int ret;
+ out_ref = av_hwframe_ctx_alloc(device_ctx);
+ if (!out_ref)
+ return AVERROR(ENOMEM);
+ out_ctx = (AVHWFramesContext *)out_ref->data;
+ out_ctx->format = AV_PIX_FMT_CUDA;
+ out_ctx->sw_format = s->out_fmt;
+ out_ctx->width = width;
+ out_ctx->height = height;
+ ret = av_hwframe_ctx_init(out_ref);
+ if (ret < 0)
+ goto fail;
+ av_frame_unref(s->frame);
+ ret = av_hwframe_get_buffer(out_ref, s->frame, 0);
+ if (ret < 0)
+ goto fail;
+ av_buffer_unref(&s->frames_ctx);
+ s->frames_ctx = out_ref;
+ return 0;
+fail:
+ av_buffer_unref(&out_ref);
+ return ret;
+}
+
+static int format_is_supported(enum AVPixelFormat fmt)
+{
+ int i;
+ for (i = 0; i < FF_ARRAY_ELEMS(supported_formats); i++)
+ if (supported_formats[i] == fmt)
+ return 1;
+ return 0;
+}
+
+static av_cold void set_format_info(AVFilterContext *ctx, enum AVPixelFormat in_format, enum AVPixelFormat out_format)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ int i, p, d;
+ s->in_fmt = in_format;
+ s->out_fmt = out_format;
+ s->in_desc = av_pix_fmt_desc_get(s->in_fmt);
+ s->out_desc = av_pix_fmt_desc_get(s->out_fmt);
+ s->in_planes = av_pix_fmt_count_planes(s->in_fmt);
+ s->out_planes = av_pix_fmt_count_planes(s->out_fmt);
+ // find maximum step of each component of each plane
+ // For our subset of formats, this should accurately tell us how many channels CUDA needs
+ // i.e. 1 for Y plane, 2 for UV plane of NV12, 4 for single plane of RGB0 formats
+ for (i = 0; i < s->in_desc->nb_components; i++)
+ {
+ d = (s->in_desc->comp[i].depth + 7) / 8;
+ p = s->in_desc->comp[i].plane;
+ s->in_plane_channels[p] = FFMAX(s->in_plane_channels[p], s->in_desc->comp[i].step / d);
+ s->in_plane_depths[p] = s->in_desc->comp[i].depth;
+ }
+}
+
+static av_cold int init_processing_chain(AVFilterContext *ctx, int width, int height)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ AVHWFramesContext *in_frames_ctx;
+ int ret;
+ /* check that we have a hw context */
+ if (!ctx->inputs[0]->hw_frames_ctx)
+ {
+ av_log(ctx, AV_LOG_ERROR, "No hw context provided on input\n");
+ return AVERROR(EINVAL);
+ }
+ in_frames_ctx = (AVHWFramesContext *)ctx->inputs[0]->hw_frames_ctx->data;
+ if (!format_is_supported(in_frames_ctx->sw_format))
+ {
+ av_log(ctx, AV_LOG_ERROR, "Unsupported format: %s\n", av_get_pix_fmt_name(in_frames_ctx->sw_format));
+ return AVERROR(ENOSYS);
+ }
+ set_format_info(ctx, in_frames_ctx->sw_format, AV_PIX_FMT_YUVA420P);
+ ret = init_hwframe_ctx(s, in_frames_ctx->device_ref, width, height);
+ if (ret < 0)
+ return ret;
+ ctx->outputs[0]->hw_frames_ctx = av_buffer_ref(s->frames_ctx);
+ if (!ctx->outputs[0]->hw_frames_ctx)
+ return AVERROR(ENOMEM);
+
+ return 0;
+}
+
+static av_cold int cudachromakey_load_functions(AVFilterContext *ctx)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ CUcontext context, cuda_ctx = s->hwctx->cuda_ctx;
+ CudaFunctions *cu = s->hwctx->internal->cuda_dl;
+ int ret;
+ extern const unsigned char ff_vf_chromakey_cuda_ptx_data[];
+ extern const unsigned int ff_vf_chromakey_cuda_ptx_len;
+ ret = CHECK_CU(cu->cuCtxPushCurrent(cuda_ctx));
+ if (ret < 0)
+ return ret;
+ ret = ff_cuda_load_module(ctx, s->hwctx, &s->cu_module,
+ ff_vf_chromakey_cuda_ptx_data, ff_vf_chromakey_cuda_ptx_len);
+ if (ret < 0)
+ goto fail;
+ ret = CHECK_CU(cu->cuModuleGetFunction(&s->cu_func, s->cu_module, "Process_uchar"));
+ if (ret < 0)
+ {
+ av_log(ctx, AV_LOG_FATAL, "Failed loading Process_uchar\n");
+ goto fail;
+ }
+ ret = CHECK_CU(cu->cuModuleGetFunction(&s->cu_func_uv, s->cu_module, "Process_uchar2"));
+ if (ret < 0)
+ {
+ av_log(ctx, AV_LOG_FATAL, "Failed loading Process_uchar2\n");
+ goto fail;
+ }
+fail:
+ CHECK_CU(cu->cuCtxPopCurrent(&context));
+
+ return ret;
+}
+
+static av_cold int cudachromakey_config_props(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ AVFilterLink *inlink = outlink->src->inputs[0];
+ ChromakeyCUDAContext *s = ctx->priv;
+ AVHWFramesContext *frames_ctx = (AVHWFramesContext *)inlink->hw_frames_ctx->data;
+ AVCUDADeviceContext *device_hwctx = frames_ctx->device_ctx->hwctx;
+ int ret;
+ s->hwctx = device_hwctx;
+ s->cu_stream = s->hwctx->stream;
+ ret = init_processing_chain(ctx, inlink->w, inlink->h);
+ if (ret < 0)
+ return ret;
+ outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
+ ret = cudachromakey_load_functions(ctx);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int call_cuda_kernel(AVFilterContext *ctx, CUfunction func,
+ CUtexObject src_tex[3], AVFrame *out_frame,
+ int width, int height, int pitch,
+ int width_uv, int height_uv, int pitch_uv,
+ float u_key, float v_key, float similarity,
+ float blend)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ CudaFunctions *cu = s->hwctx->internal->cuda_dl;
+ int ret;
+ CUdeviceptr dst_devptr[4] = {
+ (CUdeviceptr)out_frame->data[0], (CUdeviceptr)out_frame->data[1],
+ (CUdeviceptr)out_frame->data[2], (CUdeviceptr)out_frame->data[3]
+ };
+
+ void *args_uchar[] = {
+ &src_tex[0], &src_tex[1], &src_tex[2],
+ &dst_devptr[0], &dst_devptr[1], &dst_devptr[2], &dst_devptr[3],
+ &width, &height, &pitch,
+ &width_uv, &height_uv, &pitch_uv, &u_key, &v_key, &similarity, &blend};
+
+ ret = CHECK_CU(cu->cuLaunchKernel(func,
+ DIV_UP(width, BLOCKX), DIV_UP(height, BLOCKY), 1,
+ BLOCKX, BLOCKY, 1, 0, s->cu_stream, args_uchar, NULL));
+ if (ret < 0)
+ return ret;
+ // This ruins performance, but catches errors that happened in the Kernel immediately
+ // Remove for performance/production test
+ ret = CHECK_CU(cu->cuStreamSynchronize(s->cu_stream));
+
+ return ret;
+}
+
+static int cudachromakey_process_internal(AVFilterContext *ctx,
+ AVFrame *out, AVFrame *in)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ CudaFunctions *cu = s->hwctx->internal->cuda_dl;
+ CUcontext context, cuda_ctx = s->hwctx->cuda_ctx;
+ float u_key, v_key;
+ int i, ret;
+ CUtexObject tex[3] = {0, 0, 0};
+ if (s->is_yuv)
+ {
+ u_key = s->chromakey_rgba[1];
+ v_key = s->chromakey_rgba[2];
+ }
+ else
+ {
+ u_key = RGB_TO_U(s->chromakey_rgba);
+ v_key = RGB_TO_V(s->chromakey_rgba);
+ }
+ ret = CHECK_CU(cu->cuCtxPushCurrent(cuda_ctx));
+ if (ret < 0)
+ return ret;
+ for (i = 0; i < s->in_planes; i++)
+ {
+ CUDA_TEXTURE_DESC tex_desc = {
+ .filterMode = CU_TR_FILTER_MODE_LINEAR,
+ .flags = 0, // CU_TRSF_READ_AS_INTEGER to get raw ints instead of normalized floats from tex2D
+ };
+ CUDA_RESOURCE_DESC res_desc = {
+ .resType = CU_RESOURCE_TYPE_PITCH2D,
+ .res.pitch2D.format = CU_AD_FORMAT_UNSIGNED_INT8,
+ .res.pitch2D.numChannels = s->in_plane_channels[i],
+ .res.pitch2D.pitchInBytes = in->linesize[i],
+ .res.pitch2D.devPtr = (CUdeviceptr)in->data[i],
+ };
+ if (i == 1 || i == 2)
+ {
+ res_desc.res.pitch2D.width = AV_CEIL_RSHIFT(in->width, s->in_desc->log2_chroma_w);
+ res_desc.res.pitch2D.height = AV_CEIL_RSHIFT(in->height, s->in_desc->log2_chroma_h);
+ }
+ else
+ {
+ res_desc.res.pitch2D.width = in->width;
+ res_desc.res.pitch2D.height = in->height;
+ }
+ ret = CHECK_CU(cu->cuTexObjectCreate(&tex[i], &res_desc, &tex_desc, NULL));
+ if (ret < 0)
+ goto exit;
+ }
+ ret = call_cuda_kernel(ctx, (s->in_plane_channels[1] > 1) ? s->cu_func_uv : s->cu_func,
+ tex, out,
+ out->width, out->height, out->linesize[0],
+ AV_CEIL_RSHIFT(out->width, s->out_desc->log2_chroma_w),
+ AV_CEIL_RSHIFT(out->height, s->out_desc->log2_chroma_h),
+ out->linesize[1],
+ u_key, v_key, s->similarity, s->blend);
+ if (ret < 0)
+ goto exit;
+exit:
+ for (i = 0; i < s->in_planes; i++)
+ if (tex[i])
+ CHECK_CU(cu->cuTexObjectDestroy(tex[i]));
+ CHECK_CU(cu->cuCtxPopCurrent(&context));
+ return ret;
+}
+
+static int cudachromakey_process(AVFilterContext *ctx, AVFrame *out, AVFrame *in)
+{
+ ChromakeyCUDAContext *s = ctx->priv;
+ AVFrame *src = in;
+ int ret;
+ ret = cudachromakey_process_internal(ctx, s->frame, src);
+ if (ret < 0)
+ return ret;
+ src = s->frame; ret = av_hwframe_get_buffer(src->hw_frames_ctx, s->tmp_frame, 0);
+ if (ret < 0)
+ return ret;
+ av_frame_move_ref(out, s->frame);
+ av_frame_move_ref(s->frame, s->tmp_frame);
+ ret = av_frame_copy_props(out, in);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int cudachromakey_filter_frame(AVFilterLink *link, AVFrame *in)
+{
+ AVFilterContext *ctx = link->dst;
+ ChromakeyCUDAContext *s = ctx->priv;
+ AVFilterLink *outlink = ctx->outputs[0];
+ CudaFunctions *cu = s->hwctx->internal->cuda_dl;
+ AVFrame *out = NULL;
+ CUcontext context;
+ int ret = 0;
+ out = av_frame_alloc();
+ if (!out)
+ {
+ ret = AVERROR(ENOMEM);
+ goto fail;
+ }
+ ret = CHECK_CU(cu->cuCtxPushCurrent(s->hwctx->cuda_ctx));
+ if (ret < 0)
+ goto fail;
+ ret = cudachromakey_process(ctx, out, in);
+ CHECK_CU(cu->cuCtxPopCurrent(&context));
+ if (ret < 0)
+ goto fail;
+ av_frame_free(&in);
+ return ff_filter_frame(outlink, out);
+fail:
+ av_frame_free(&in);
+ av_frame_free(&out);
+ return ret;
+}
+
+static AVFrame *cudachromakey_get_video_buffer(AVFilterLink *inlink, int w, int h)
+{
+ return ff_default_get_video_buffer(inlink, w, h);
+}
+
+#define OFFSET(x) offsetof(ChromakeyCUDAContext, x)
+#define FLAGS (AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
+static const AVOption options[] = {
+ {"color", "set the chromakey key color", OFFSET(chromakey_rgba), AV_OPT_TYPE_COLOR, {.str = "black"}, 0, 0, FLAGS},
+ {"similarity", "set the chromakey similarity value", OFFSET(similarity), AV_OPT_TYPE_FLOAT, {.dbl = 0.01}, 0.01, 1.0, FLAGS},
+ {"blend", "set the chromakey key blend value", OFFSET(blend), AV_OPT_TYPE_FLOAT, {.dbl = 0.0}, 0.0, 1.0, FLAGS},
+ {"yuv", "color parameter is in yuv instead of rgb", OFFSET(is_yuv), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, FLAGS},
+ {"w", "Output video width", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, .flags = FLAGS},
+ {"h", "Output video height", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, .flags = FLAGS},
+ {NULL},
+};
+
+static const AVClass cudachromakey_class = {
+ .class_name = "cudachromakey",
+ .item_name = av_default_item_name,
+ .option = options,
+ .version = LIBAVUTIL_VERSION_INT,
+};
+
+static const AVFilterPad cudachromakey_inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .filter_frame = cudachromakey_filter_frame,
+ .get_buffer.video = cudachromakey_get_video_buffer,
+ },
+};
+
+static const AVFilterPad cudachromakey_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = cudachromakey_config_props,
+ },
+};
+
+const AVFilter ff_vf_chromakey_cuda = {
+ .name = "chromakey_cuda",
+ .description = NULL_IF_CONFIG_SMALL("GPU accelerated chromakey filter"),
+ .init = cudachromakey_init,
+ .uninit = cudachromakey_uninit,
+ .priv_size = sizeof(ChromakeyCUDAContext),
+ .priv_class = &cudachromakey_class,
+ FILTER_INPUTS(cudachromakey_inputs),
+ FILTER_OUTPUTS(cudachromakey_outputs),
+ FILTER_SINGLE_PIXFMT(AV_PIX_FMT_CUDA),
+ .flags_internal = FF_FILTER_FLAG_HWFRAME_AWARE,
+};
diff --git a/libavfilter/vf_chromakey_cuda.cu b/libavfilter/vf_chromakey_cuda.cu
new file mode 100644
index 0000000000..f6e7a80c42
--- /dev/null
+++ b/libavfilter/vf_chromakey_cuda.cu
@@ -0,0 +1,164 @@
+/*
+ * Copyright (c) 2022 Mohamed Khaled <Mohamed_Khaled_Kamal at outlook.com>
+ *
+ * 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 "cuda/vector_helpers.cuh"
+
+extern "C"
+{
+/**
+ * @brief function contains the main logic of chroma keying, and changes the alpahc channel with the suitable value
+ *
+ * @param src_tex texture U or texture UV , decided based on the passed is_uchar2 flag
+ * @param src_tex_V texture V , used only if is_uchar2 flag is false
+ * @param dst_A alpha channel destination
+ * @param width_uv width of uv channels
+ * @param height_uv height of uv channels
+ * @param width width of alpha channel
+ * @param height height of alpha channel
+ * @param pitch pitch of alpha channel
+ * @param x current x coordinate of pixel
+ * @param y current y coordinate of pixel
+ * @param chromakey_uv uv values for chroma keying
+ * @param similarity similarity of keying
+ * @param blend blend of keying
+ * @return void
+ */
+__device__ static inline void change_alpha_channel(
+ cudaTextureObject_t src_tex, cudaTextureObject_t src_tex_V, uchar *dst_A,
+ int width_uv, int height_uv,
+ int width, int height, int pitch,
+ int x, int y,
+ float2 chromakey_uv, float similarity,float blend)
+{
+ uchar window_size = 3;
+ int start_r = x - window_size / 2;
+ int start_c = y - window_size / 2;
+ int resize_ratio = width / width_uv;
+ uchar counter = 0;
+ float diff = 0.0f;
+ float du, dv;
+
+ // loop over the eight neighbourhood of the current pixel(x,y)
+ for (uchar i = 0; i < window_size; i++)
+ {
+ for (uchar j = 0; j < window_size; j++)
+ {
+ int r = start_r + i;
+ int c = start_c + j;
+ bool check_flag = (r >= 0 && r < width_uv && c >= 0 && c < height_uv);
+ if (!check_flag)
+ continue;
+ float u_value, v_value;
+ if (!src_tex_V){
+ float2 temp_uv = tex2D<float2>(src_tex, r, c);
+ u_value = temp_uv.x;
+ v_value = temp_uv.y;
+ }else{
+ u_value = tex2D<float>(src_tex, r, c);
+ v_value = tex2D<float>(src_tex_V, r, c);
+ }
+ du = (u_value * 255.0f) - chromakey_uv.x;
+ dv = (v_value * 255.0f) - chromakey_uv.y;
+ diff += sqrtf((du * du + dv * dv) / (255.0f * 255.0f * 2.f));
+ counter++;
+ }
+ }
+
+ if (counter > 0)
+ diff = diff / counter;
+ else
+ diff /= 9.0f;
+
+ uchar alpha_value;
+ if (blend>0.0001f)
+ alpha_value=__saturatef((diff - similarity) / blend)*255;
+ else
+ alpha_value=(diff < similarity ? 0 : 1)*255;
+
+ //write the value in the alpha channel with regarding the ratio of (alpha_size : uv_size)
+ for (uchar k = 0; k < resize_ratio; k++)
+ {
+ for (uchar l = 0; l < resize_ratio; l++)
+ {
+ int x_resize = x * resize_ratio + k;
+ int y_resize = y * resize_ratio + l;
+ int a_channel_resize = y_resize * pitch + x_resize;
+ if (y_resize >= height || x_resize >= width)
+ continue;
+ dst_A[a_channel_resize] = alpha_value;
+ }
+ }
+}
+
+__global__ void Process_uchar(
+ cudaTextureObject_t src_tex_Y, cudaTextureObject_t src_tex_U, cudaTextureObject_t src_tex_V,
+ uchar *dst_Y, uchar *dst_U, uchar *dst_V, uchar *dst_A,
+ int width, int height, int pitch,
+ int width_uv, int height_uv, int pitch_uv,
+ float u_key, float v_key, float similarity,float blend)
+{
+ int x = blockIdx.x * blockDim.x + threadIdx.x;
+ int y = blockIdx.y * blockDim.y + threadIdx.y;
+
+ if (y >= height || x >= width)
+ return;
+ dst_Y[y * pitch + x] = tex2D<float>(src_tex_Y, x, y)*255;
+ if (y >= height_uv || x >= width_uv)
+ return;
+
+ int uv_index = y * pitch_uv + x;
+ dst_U[uv_index]=tex2D<float>(src_tex_U,x,y)*255;
+ dst_V[uv_index]=tex2D<float>(src_tex_V,x,y)*255;
+
+ change_alpha_channel(src_tex_U, src_tex_V, dst_A,
+ width_uv, height_uv,
+ width, height, pitch,
+ x, y,
+ make_float2(u_key,v_key), similarity, blend);
+}
+
+__global__ void Process_uchar2(
+ cudaTextureObject_t src_tex_Y, cudaTextureObject_t src_tex_UV, cudaTextureObject_t unused1,
+ uchar *dst_Y, uchar *dst_U, uchar *dst_V, uchar *dst_A,
+ int width, int height, int pitch,
+ int width_uv, int height_uv,int pitch_uv,
+ float u_key,float v_key, float similarity, float blend)
+{
+ int x = blockIdx.x * blockDim.x + threadIdx.x; // x coordinate of current pixel
+ int y = blockIdx.y * blockDim.y + threadIdx.y; // y coordinate of current pixel
+
+ if (y >= height || x >= width)
+ return;
+ dst_Y[y * pitch + x] = tex2D<float>(src_tex_Y, x, y)*255;
+
+ if (y >= height_uv || x >= width_uv)
+ return;
+ int uv_index = y * pitch_uv + x;
+ float2 uv_temp =tex2D<float2>(src_tex_UV,x,y);
+ dst_U[uv_index]=uv_temp.x*255;
+ dst_V[uv_index]=uv_temp.y*255;
+
+ change_alpha_channel(src_tex_UV, (cudaTextureObject_t)nullptr,
+ dst_A, width_uv, height_uv,
+ width,height, pitch,
+ x, y,
+ make_float2(u_key,v_key), similarity,blend);
+}
+}
--
2.36.1
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