| /* |
| * Copyright (c) 2017 Vittorio Giovara <vittorio.giovara@gmail.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 |
| */ |
| |
| /** |
| * @file |
| * tonemap algorithms |
| */ |
| |
| #include <float.h> |
| #include <stdio.h> |
| #include <string.h> |
| |
| #include "libavutil/imgutils.h" |
| #include "libavutil/internal.h" |
| #include "libavutil/intreadwrite.h" |
| #include "libavutil/mastering_display_metadata.h" |
| #include "libavutil/opt.h" |
| #include "libavutil/pixdesc.h" |
| |
| #include "avfilter.h" |
| #include "formats.h" |
| #include "internal.h" |
| #include "video.h" |
| |
| #define REFERENCE_WHITE 100.0f |
| |
| enum TonemapAlgorithm { |
| TONEMAP_NONE, |
| TONEMAP_LINEAR, |
| TONEMAP_GAMMA, |
| TONEMAP_CLIP, |
| TONEMAP_REINHARD, |
| TONEMAP_HABLE, |
| TONEMAP_MOBIUS, |
| TONEMAP_MAX, |
| }; |
| |
| typedef struct LumaCoefficients { |
| double cr, cg, cb; |
| } LumaCoefficients; |
| |
| |
| static const struct LumaCoefficients luma_coefficients[AVCOL_SPC_NB] = { |
| [AVCOL_SPC_FCC] = { 0.30, 0.59, 0.11 }, |
| [AVCOL_SPC_BT470BG] = { 0.299, 0.587, 0.114 }, |
| [AVCOL_SPC_SMPTE170M] = { 0.299, 0.587, 0.114 }, |
| [AVCOL_SPC_BT709] = { 0.2126, 0.7152, 0.0722 }, |
| [AVCOL_SPC_SMPTE240M] = { 0.212, 0.701, 0.087 }, |
| [AVCOL_SPC_BT2020_NCL] = { 0.2627, 0.6780, 0.0593 }, |
| [AVCOL_SPC_BT2020_CL] = { 0.2627, 0.6780, 0.0593 }, |
| }; |
| |
| typedef struct TonemapContext { |
| const AVClass *class; |
| |
| enum TonemapAlgorithm tonemap; |
| double param; |
| double desat; |
| double peak; |
| |
| const LumaCoefficients *coeffs; |
| } TonemapContext; |
| |
| static const enum AVPixelFormat pix_fmts[] = { |
| AV_PIX_FMT_GBRPF32, |
| AV_PIX_FMT_GBRAPF32, |
| AV_PIX_FMT_NONE, |
| }; |
| |
| static int query_formats(AVFilterContext *ctx) |
| { |
| return ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| } |
| |
| static av_cold int init(AVFilterContext *ctx) |
| { |
| TonemapContext *s = ctx->priv; |
| |
| switch(s->tonemap) { |
| case TONEMAP_GAMMA: |
| if (isnan(s->param)) |
| s->param = 1.8f; |
| break; |
| case TONEMAP_REINHARD: |
| if (!isnan(s->param)) |
| s->param = (1.0f - s->param) / s->param; |
| break; |
| case TONEMAP_MOBIUS: |
| if (isnan(s->param)) |
| s->param = 0.3f; |
| break; |
| } |
| |
| if (isnan(s->param)) |
| s->param = 1.0f; |
| |
| return 0; |
| } |
| |
| static double determine_signal_peak(AVFrame *in) |
| { |
| AVFrameSideData *sd = av_frame_get_side_data(in, AV_FRAME_DATA_CONTENT_LIGHT_LEVEL); |
| double peak = 0; |
| |
| if (sd) { |
| AVContentLightMetadata *clm = (AVContentLightMetadata *)sd->data; |
| peak = clm->MaxCLL / REFERENCE_WHITE; |
| } |
| |
| sd = av_frame_get_side_data(in, AV_FRAME_DATA_MASTERING_DISPLAY_METADATA); |
| if (!peak && sd) { |
| AVMasteringDisplayMetadata *metadata = (AVMasteringDisplayMetadata *)sd->data; |
| if (metadata->has_luminance) |
| peak = av_q2d(metadata->max_luminance) / REFERENCE_WHITE; |
| } |
| |
| /* smpte2084 needs the side data above to work correctly |
| * if missing, assume that the original transfer was arib-std-b67 */ |
| if (!peak) |
| peak = 12; |
| |
| return peak; |
| } |
| |
| static float hable(float in) |
| { |
| float a = 0.15f, b = 0.50f, c = 0.10f, d = 0.20f, e = 0.02f, f = 0.30f; |
| return (in * (in * a + b * c) + d * e) / (in * (in * a + b) + d * f) - e / f; |
| } |
| |
| static float mobius(float in, float j, double peak) |
| { |
| float a, b; |
| |
| if (in <= j) |
| return in; |
| |
| a = -j * j * (peak - 1.0f) / (j * j - 2.0f * j + peak); |
| b = (j * j - 2.0f * j * peak + peak) / FFMAX(peak - 1.0f, 1e-6); |
| |
| return (b * b + 2.0f * b * j + j * j) / (b - a) * (in + a) / (in + b); |
| } |
| |
| #define MIX(x,y,a) (x) * (1 - (a)) + (y) * (a) |
| static void tonemap(TonemapContext *s, AVFrame *out, const AVFrame *in, |
| const AVPixFmtDescriptor *desc, int x, int y, double peak) |
| { |
| const float *r_in = (const float *)(in->data[0] + x * desc->comp[0].step + y * in->linesize[0]); |
| const float *b_in = (const float *)(in->data[1] + x * desc->comp[1].step + y * in->linesize[1]); |
| const float *g_in = (const float *)(in->data[2] + x * desc->comp[2].step + y * in->linesize[2]); |
| float *r_out = (float *)(out->data[0] + x * desc->comp[0].step + y * out->linesize[0]); |
| float *b_out = (float *)(out->data[1] + x * desc->comp[1].step + y * out->linesize[1]); |
| float *g_out = (float *)(out->data[2] + x * desc->comp[2].step + y * out->linesize[2]); |
| float sig, sig_orig; |
| |
| /* load values */ |
| *r_out = *r_in; |
| *b_out = *b_in; |
| *g_out = *g_in; |
| |
| /* desaturate to prevent unnatural colors */ |
| if (s->desat > 0) { |
| float luma = s->coeffs->cr * *r_in + s->coeffs->cg * *g_in + s->coeffs->cb * *b_in; |
| float overbright = FFMAX(luma - s->desat, 1e-6) / FFMAX(luma, 1e-6); |
| *r_out = MIX(*r_in, luma, overbright); |
| *g_out = MIX(*g_in, luma, overbright); |
| *b_out = MIX(*b_in, luma, overbright); |
| } |
| |
| /* pick the brightest component, reducing the value range as necessary |
| * to keep the entire signal in range and preventing discoloration due to |
| * out-of-bounds clipping */ |
| sig = FFMAX(FFMAX3(*r_out, *g_out, *b_out), 1e-6); |
| sig_orig = sig; |
| |
| switch(s->tonemap) { |
| default: |
| case TONEMAP_NONE: |
| // do nothing |
| break; |
| case TONEMAP_LINEAR: |
| sig = sig * s->param / peak; |
| break; |
| case TONEMAP_GAMMA: |
| sig = sig > 0.05f ? pow(sig / peak, 1.0f / s->param) |
| : sig * pow(0.05f / peak, 1.0f / s->param) / 0.05f; |
| break; |
| case TONEMAP_CLIP: |
| sig = av_clipf(sig * s->param, 0, 1.0f); |
| break; |
| case TONEMAP_HABLE: |
| sig = hable(sig) / hable(peak); |
| break; |
| case TONEMAP_REINHARD: |
| sig = sig / (sig + s->param) * (peak + s->param) / peak; |
| break; |
| case TONEMAP_MOBIUS: |
| sig = mobius(sig, s->param, peak); |
| break; |
| } |
| |
| /* apply the computed scale factor to the color, |
| * linearly to prevent discoloration */ |
| *r_out *= sig / sig_orig; |
| *g_out *= sig / sig_orig; |
| *b_out *= sig / sig_orig; |
| } |
| |
| static int filter_frame(AVFilterLink *link, AVFrame *in) |
| { |
| TonemapContext *s = link->dst->priv; |
| AVFilterLink *outlink = link->dst->outputs[0]; |
| AVFrame *out; |
| const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format); |
| const AVPixFmtDescriptor *odesc = av_pix_fmt_desc_get(outlink->format); |
| int ret, x, y; |
| double peak = s->peak; |
| |
| if (!desc || !odesc) { |
| av_frame_free(&in); |
| return AVERROR_BUG; |
| } |
| |
| out = ff_get_video_buffer(outlink, outlink->w, outlink->h); |
| if (!out) { |
| av_frame_free(&in); |
| return AVERROR(ENOMEM); |
| } |
| |
| ret = av_frame_copy_props(out, in); |
| if (ret < 0) { |
| av_frame_free(&in); |
| av_frame_free(&out); |
| return ret; |
| } |
| |
| /* input and output transfer will be linear */ |
| if (in->color_trc == AVCOL_TRC_UNSPECIFIED) { |
| av_log(s, AV_LOG_WARNING, "Untagged transfer, assuming linear light\n"); |
| out->color_trc = AVCOL_TRC_LINEAR; |
| } else if (in->color_trc != AVCOL_TRC_LINEAR) |
| av_log(s, AV_LOG_WARNING, "Tonemapping works on linear light only\n"); |
| |
| /* read peak from side data if not passed in */ |
| if (!peak) { |
| peak = determine_signal_peak(in); |
| av_log(s, AV_LOG_DEBUG, "Computed signal peak: %f\n", peak); |
| } |
| |
| /* load original color space even if pixel format is RGB to compute overbrights */ |
| s->coeffs = &luma_coefficients[in->colorspace]; |
| if (s->desat > 0 && (in->colorspace == AVCOL_SPC_UNSPECIFIED || !s->coeffs)) { |
| if (in->colorspace == AVCOL_SPC_UNSPECIFIED) |
| av_log(s, AV_LOG_WARNING, "Missing color space information, "); |
| else if (!s->coeffs) |
| av_log(s, AV_LOG_WARNING, "Unsupported color space '%s', ", |
| av_color_space_name(in->colorspace)); |
| av_log(s, AV_LOG_WARNING, "desaturation is disabled\n"); |
| s->desat = 0; |
| } |
| |
| /* do the tone map */ |
| for (y = 0; y < out->height; y++) |
| for (x = 0; x < out->width; x++) |
| tonemap(s, out, in, desc, x, y, peak); |
| |
| /* copy/generate alpha if needed */ |
| if (desc->flags & AV_PIX_FMT_FLAG_ALPHA && odesc->flags & AV_PIX_FMT_FLAG_ALPHA) { |
| av_image_copy_plane(out->data[3], out->linesize[3], |
| in->data[3], in->linesize[3], |
| out->linesize[3], outlink->h); |
| } else if (odesc->flags & AV_PIX_FMT_FLAG_ALPHA) { |
| for (y = 0; y < out->height; y++) { |
| for (x = 0; x < out->width; x++) { |
| AV_WN32(out->data[3] + x * odesc->comp[3].step + y * out->linesize[3], |
| av_float2int(1.0f)); |
| } |
| } |
| } |
| |
| av_frame_free(&in); |
| |
| return ff_filter_frame(outlink, out); |
| } |
| |
| #define OFFSET(x) offsetof(TonemapContext, x) |
| #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM |
| static const AVOption tonemap_options[] = { |
| { "tonemap", "tonemap algorithm selection", OFFSET(tonemap), AV_OPT_TYPE_INT, {.i64 = TONEMAP_NONE}, TONEMAP_NONE, TONEMAP_MAX - 1, FLAGS, "tonemap" }, |
| { "none", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_NONE}, 0, 0, FLAGS, "tonemap" }, |
| { "linear", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_LINEAR}, 0, 0, FLAGS, "tonemap" }, |
| { "gamma", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_GAMMA}, 0, 0, FLAGS, "tonemap" }, |
| { "clip", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_CLIP}, 0, 0, FLAGS, "tonemap" }, |
| { "reinhard", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_REINHARD}, 0, 0, FLAGS, "tonemap" }, |
| { "hable", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_HABLE}, 0, 0, FLAGS, "tonemap" }, |
| { "mobius", 0, 0, AV_OPT_TYPE_CONST, {.i64 = TONEMAP_MOBIUS}, 0, 0, FLAGS, "tonemap" }, |
| { "param", "tonemap parameter", OFFSET(param), AV_OPT_TYPE_DOUBLE, {.dbl = NAN}, DBL_MIN, DBL_MAX, FLAGS }, |
| { "desat", "desaturation strength", OFFSET(desat), AV_OPT_TYPE_DOUBLE, {.dbl = 2}, 0, DBL_MAX, FLAGS }, |
| { "peak", "signal peak override", OFFSET(peak), AV_OPT_TYPE_DOUBLE, {.dbl = 0}, 0, DBL_MAX, FLAGS }, |
| { NULL } |
| }; |
| |
| static const AVClass tonemap_class = { |
| .class_name = "tonemap", |
| .item_name = av_default_item_name, |
| .option = tonemap_options, |
| .version = LIBAVUTIL_VERSION_INT, |
| .category = AV_CLASS_CATEGORY_FILTER, |
| }; |
| |
| static const AVFilterPad tonemap_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .filter_frame = filter_frame, |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad tonemap_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| }, |
| { NULL } |
| }; |
| |
| AVFilter ff_vf_tonemap = { |
| .name = "tonemap", |
| .description = NULL_IF_CONFIG_SMALL("Conversion to/from different dynamic ranges."), |
| .init = init, |
| .query_formats = query_formats, |
| .priv_size = sizeof(TonemapContext), |
| .priv_class = &tonemap_class, |
| .inputs = tonemap_inputs, |
| .outputs = tonemap_outputs, |
| }; |
