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avfilter/tonemap_*: better documentation for constants
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@gnattu
gnattu committed Oct 13, 2024
1 parent 1dd26f0 commit 669c8de
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Showing 3 changed files with 68 additions and 33 deletions.
54 changes: 42 additions & 12 deletions debian/patches/0004-add-cuda-tonemap-impl.patch
View file
Original file line number Diff line number Diff line change
Expand Up @@ -257,7 +257,7 @@ Index: FFmpeg/libavfilter/colorspace.h
===================================================================
--- FFmpeg.orig/libavfilter/colorspace.h
+++ FFmpeg/libavfilter/colorspace.h
@@ -23,10 +23,42 @@
@@ -23,10 +23,69 @@
#include "libavutil/csp.h"
#include "libavutil/frame.h"
#include "libavutil/pixfmt.h"
Expand All @@ -276,6 +276,33 @@ Index: FFmpeg/libavfilter/colorspace.h
+#define ARIB_B67_C 0.55991073f
+#define FLOAT_EPS 1e-6f
+
+/*
+ * Pre-calculated constants used for YCbCr narrow to full range scaling
+ * The base formula is the quantization formula derived from BT.2100 Table 9:
+ * Where Y' = Round [(219 * E′ + 16) * 2^(n−8)],
+ * Cb',Cr' = Round [(224 * E′ + 128) * 2^(n−8)]
+ * where E' is the signal value in [0,1] range and n is the bit depth. Round is rounding towards 0.
+ * For inputs, the inverse is used where we are solving for E' for a given Y'Cb'Cr' normalized by GPU
+ * in [0,1] range. The GPU will interpret color as a 16bit int value, and solving for E' becomes:
+ * E' = (Y' - 2^(n-4)) / (219 * 2^(n-8))
+ * E' = (Cb'Cr' - 2^(n-1)) / (7 * 2^(n-3))
+ * Y' and Cb'Cr' is in the range of [0, 2^n - 1] in original formula, we need to scale the value normalized to [0,1]:
+ * C = Y'Cb'Cr' * (2^n - 1)
+ * Which means the input scale = (2^n - 1) / (219 * 2^(n-8)) and input offset = 2^(n-4)) / (219 * 2^(n-8)) for Y' and
+ * 2^(n-1)) / (7 * 2^(n-3)) for Cb'Cr'
+ */
+#define INPUT_Y_SCALE_10B 1.1678082192f
+#define INPUT_UV_SCALE_10B 1.1417410714f
+#define INPUT_Y_SCALE_12B 1.1689497717f
+#define INPUT_UV_SCALE_12B 1.1428571429f
+
+/*
+ * GPU will interpret 10bit and 12bit color as 16bit int
+ * but that will introduce a slight (2^(16-n))/2^16 quantization offset which we want to compensate for
+*/
+#define QUANTIZATION_OFFSET_10B 0.0009765774014f
+#define QUANTIZATION_OFFSET_12B 0.0002441443503f
+
+// Parsed metadata from the Dolby Vision RPU
+struct DoviMetadata {
+ float nonlinear_offset[3]; // input offset ("ycc_to_rgb_offset")
Expand All @@ -300,7 +327,7 @@ Index: FFmpeg/libavfilter/colorspace.h
void ff_matrix_mul_3x3(double dst[3][3],
const double src1[3][3], const double src2[3][3]);
void ff_matrix_mul_3x3_vec(double dst[3], const double vec[3], const double mat[3][3]);
@@ -38,4 +70,19 @@ void ff_fill_rgb2yuv_table(const AVLumaC
@@ -38,4 +97,19 @@ void ff_fill_rgb2yuv_table(const AVLumaC
double ff_determine_signal_peak(AVFrame *in);
void ff_update_hdr_metadata(AVFrame *in, double peak);

Expand Down Expand Up @@ -1785,7 +1812,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_cuda.c
===================================================================
--- /dev/null
+++ FFmpeg/libavfilter/vf_tonemap_cuda.c
@@ -0,0 +1,1162 @@
@@ -0,0 +1,1165 @@
+/*
+ * This file is part of FFmpeg.
+ *
Expand Down Expand Up @@ -2413,22 +2440,25 @@ Index: FFmpeg/libavfilter/vf_tonemap_cuda.c
+ return ret;
+
+ if (s->in_desc->comp[0].depth == 10) {
+ input_quantization_offset = 0.0009765774014f;
+ input_y_scale = 1.1678082192f;
+ input_uv_scale = 1.1417410714f;
+ input_quantization_offset = QUANTIZATION_OFFSET_10B;
+ input_y_scale = INPUT_Y_SCALE_10B;
+ input_uv_scale = INPUT_UV_SCALE_10B;
+ } else if (s->in_desc->comp[0].depth == 16) {
+ input_quantization_offset = 0.0002441443503f;
+ input_y_scale = 1.1689497717f;
+ input_uv_scale = 1.1428571429f;
+ // Assume 16bit is actually 12bit for now as that is what the hardware decoders producing
+ // and what videos are actually encoded in
+ input_quantization_offset = QUANTIZATION_OFFSET_12B;
+ input_y_scale = INPUT_Y_SCALE_12B;
+ input_uv_scale = INPUT_UV_SCALE_12B;
+ }
+
+ if (s->out_desc->comp[0].depth == 10) {
+ output_quantization_offset = 0.0009765774014f;
+ // Don't handle 12b offset for now and assume 16b output is real 16b out to make it consistent with other filters
+ output_quantization_offset = QUANTIZATION_OFFSET_10B;
+ }
+
+ if (s->out_desc->comp[0].depth > 8) {
+ output_quantization_factor = 256.0f;
+ output_quantization_scale = 65535.0f;
+ output_quantization_factor = 256.0f; // 2^(16-8)
+ output_quantization_scale = 65535.0f; // 2^16 - 1
+ }
+
+ av_bprint_init(&constants, 2048, AV_BPRINT_SIZE_UNLIMITED);
Expand Down
41 changes: 22 additions & 19 deletions debian/patches/0007-add-bt2390-eetf-and-code-refactor-to-opencl-tonemap.patch
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1458,7 +1458,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

switch(ctx->tonemap) {
case TONEMAP_GAMMA:
@@ -139,59 +353,207 @@ static int tonemap_opencl_init(AVFilterC
@@ -139,59 +353,210 @@ static int tonemap_opencl_init(AVFilterC
if (isnan(ctx->param))
ctx->param = 0.3f;
break;
Expand Down Expand Up @@ -1656,16 +1656,18 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c
av_bprintf(&header, "#define FULL_RANGE_OUT\n");

+ if (ctx->in_desc->comp[0].depth == 10) {
+ av_bprintf(&header, "#define INPUT_QUANTIZATION_OFFSET 0.0009765774014f\n");
+ av_bprintf(&header, "#define INPUT_Y_SCALE 1.1678082192f\n");
+ av_bprintf(&header, "#define INPUT_UV_SCALE 1.1417410714f\n");
+ av_bprintf(&header, "#define INPUT_QUANTIZATION_OFFSET %ff\n", QUANTIZATION_OFFSET_10B);
+ av_bprintf(&header, "#define INPUT_Y_SCALE %ff\n", INPUT_Y_SCALE_10B);
+ av_bprintf(&header, "#define INPUT_UV_SCALE %ff\n", INPUT_UV_SCALE_10B);
+ } else if (ctx->in_desc->comp[0].depth == 16) {
+ // 16bit texture is actually 12bit
+ av_bprintf(&header, "#define INPUT_QUANTIZATION_OFFSET 0.0002441443503f\n");
+ av_bprintf(&header, "#define INPUT_Y_SCALE 1.1689497717f\n");
+ av_bprintf(&header, "#define INPUT_UV_SCALE 1.1428571429f\n");
+ // Assume 16bit is actually 12bit for now as that is what the hardware decoders producing
+ // and what videos are actually encoded in
+ av_bprintf(&header, "#define INPUT_QUANTIZATION_OFFSET %ff\n", QUANTIZATION_OFFSET_12B);
+ av_bprintf(&header, "#define INPUT_Y_SCALE %ff\n", INPUT_Y_SCALE_12B);
+ av_bprintf(&header, "#define INPUT_UV_SCALE %ff\n", INPUT_UV_SCALE_12B);
+ } else {
+ // should not happen, but for completeness
+ // once we can tell if the input is real 16bit we can use this branch
+ av_bprintf(&header, "#define INPUT_QUANTIZATION_OFFSET 0.0f\n");
+ av_bprintf(&header, "#define INPUT_Y_SCALE 1.0f\n");
+ av_bprintf(&header, "#define INPUT_UV_SCALE 1.0f\n");
Expand All @@ -1675,13 +1677,14 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c
+ av_bprintf(&header, "#define RESCALE_LIMITED_RANGE_OUTPUT\n");
+ }
+
+ if (ctx->in_desc->comp[0].depth == 10)
+ av_bprintf(&header, "#define OUTPUT_QUANTIZATION_OFFSET 0.0009765774014f\n");
+ if (ctx->out_desc->comp[0].depth == 10)
+ av_bprintf(&header, "#define OUTPUT_QUANTIZATION_OFFSET %ff\n", QUANTIZATION_OFFSET_10B);
+ // Don't handle 12b offset for now and assume 16b output is real 16b out to make it consistent with other filters
+
av_bprintf(&header, "#define chroma_loc %d\n", (int)ctx->chroma_loc);

if (rgb2rgb_passthrough)
@@ -199,19 +561,41 @@ static int tonemap_opencl_init(AVFilterC
@@ -199,19 +564,41 @@ static int tonemap_opencl_init(AVFilterC
else
ff_opencl_print_const_matrix_3x3(&header, "rgb2rgb", rgb2rgb);

Expand Down Expand Up @@ -1730,7 +1733,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c
ctx->colorspace_out, av_color_space_name(ctx->colorspace_out));
goto fail;
}
@@ -219,24 +603,23 @@ static int tonemap_opencl_init(AVFilterC
@@ -219,24 +606,23 @@ static int tonemap_opencl_init(AVFilterC
ff_fill_rgb2yuv_table(luma_dst, rgb2yuv);
ff_opencl_print_const_matrix_3x3(&header, "yuv_matrix", rgb2yuv);

Expand Down Expand Up @@ -1770,7 +1773,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

av_log(avctx, AV_LOG_DEBUG, "Generated OpenCL header:\n%s\n", header.str);
opencl_sources[0] = header.str;
@@ -254,46 +637,171 @@ static int tonemap_opencl_init(AVFilterC
@@ -254,46 +640,171 @@ static int tonemap_opencl_init(AVFilterC
CL_FAIL_ON_ERROR(AVERROR(EIO), "Failed to create OpenCL "
"command queue %d.\n", cle);

Expand Down Expand Up @@ -1960,7 +1963,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c
ret = ff_opencl_filter_config_output(outlink);
if (ret < 0)
return ret;
@@ -308,13 +816,46 @@ static int launch_kernel(AVFilterContext
@@ -308,13 +819,46 @@ static int launch_kernel(AVFilterContext
size_t global_work[2];
size_t local_work[2];
cl_int cle;
Expand Down Expand Up @@ -2009,7 +2012,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

local_work[0] = 16;
local_work[1] = 16;
@@ -338,13 +879,10 @@ static int tonemap_opencl_filter_frame(A
@@ -338,13 +882,10 @@ static int tonemap_opencl_filter_frame(A
AVFilterContext *avctx = inlink->dst;
AVFilterLink *outlink = avctx->outputs[0];
TonemapOpenCLContext *ctx = avctx->priv;
Expand All @@ -2024,7 +2027,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

av_log(ctx, AV_LOG_DEBUG, "Filter input: %s, %ux%u (%"PRId64").\n",
av_get_pix_fmt_name(input->format),
@@ -363,8 +901,49 @@ static int tonemap_opencl_filter_frame(A
@@ -363,8 +904,49 @@ static int tonemap_opencl_filter_frame(A
if (err < 0)
goto fail;

Expand Down Expand Up @@ -2076,7 +2079,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

if (ctx->trc != -1)
output->color_trc = ctx->trc;
@@ -385,72 +964,50 @@ static int tonemap_opencl_filter_frame(A
@@ -385,72 +967,50 @@ static int tonemap_opencl_filter_frame(A
ctx->range_out = output->color_range;
ctx->chroma_loc = output->chroma_location;

Expand Down Expand Up @@ -2172,7 +2175,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c
av_frame_free(&input);
av_frame_free(&output);
return err;
@@ -458,24 +1015,9 @@ fail:
@@ -458,24 +1018,9 @@ fail:

static av_cold void tonemap_opencl_uninit(AVFilterContext *avctx)
{
Expand All @@ -2199,7 +2202,7 @@ Index: FFmpeg/libavfilter/vf_tonemap_opencl.c

ff_opencl_filter_uninit(avctx);
}
@@ -483,37 +1025,50 @@ static av_cold void tonemap_opencl_unini
@@ -483,37 +1028,50 @@ static av_cold void tonemap_opencl_unini
#define OFFSET(x) offsetof(TonemapOpenCLContext, x)
#define FLAGS (AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_VIDEO_PARAM)
static const AVOption tonemap_opencl_options[] = {
Expand Down
6 changes: 4 additions & 2 deletions debian/patches/0052-add-vf-tonemap-videotoolbox-filter.patch
View file
Original file line number Diff line number Diff line change
Expand Up @@ -40,7 +40,7 @@ Index: FFmpeg/libavfilter/metal/vf_tonemap_videotoolbox.metal
===================================================================
--- /dev/null
+++ FFmpeg/libavfilter/metal/vf_tonemap_videotoolbox.metal
@@ -0,0 +1,914 @@
@@ -0,0 +1,916 @@
+/*
+ * Copyright (c) 2024 Gnattu OC <[email protected]>
+ *
Expand Down Expand Up @@ -269,6 +269,7 @@ Index: FFmpeg/libavfilter/metal/vf_tonemap_videotoolbox.metal
+
+// ------------
+// Color conversion
+// See libavfilter/colorspace.h for derivation of these constants
+float3 yuv2rgb(float y, float u, float v) {
+ y += mix(0.0f, 0.0009765774014f, y > 0.0f);
+ u += mix(0.0f, 0.0009765774014f, u > 0.0f);
Expand Down Expand Up @@ -317,7 +318,8 @@ Index: FFmpeg/libavfilter/metal/vf_tonemap_videotoolbox.metal
+ v = floor(((224.0f * v + 128.0f) * 256.0f) + 0.5f) / 65535.0f;
+ }
+ }
+ // in rgb2yuv conversion, enable_dither means output is 8bit
+ // in rgb2yuv conversion, enable_dither means output is 8bit in metal pipeline
+ // use this to check if we need the 10bit offset
+ if (!enable_dither) {
+ y -= mix(0.0f, 0.0009765774014f, y > 0.0f);
+ u -= mix(0.0f, 0.0009765774014f, u > 0.0f);
Expand Down

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