lavfi: add vf_iccgen for generating ICC profiles

This filter is designed to specifically cover the task of generating ICC
profiles (and attaching them to output frames) on demand. Other tasks,
such as ICC profile loading/stripping, or ICC profile application, are
better left to separate filters (or included into e.g. vf_setparams).

Signed-off-by: Niklas Haas <git@haasn.dev>

3 files changed, 183 insertions, 0 deletions

diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 772454ba23..db021915fe 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -322,6 +322,7 @@ OBJS-$(CONFIG_HWMAP_FILTER)                  += vf_hwmap.o
 OBJS-$(CONFIG_HWUPLOAD_CUDA_FILTER)          += vf_hwupload_cuda.o
 OBJS-$(CONFIG_HWUPLOAD_FILTER)               += vf_hwupload.o
 OBJS-$(CONFIG_HYSTERESIS_FILTER)             += vf_hysteresis.o framesync.o
+OBJS-$(CONFIG_ICCGEN_FILTER)                 += vf_iccgen.o fflcms2.o colorspace.o
 OBJS-$(CONFIG_IDENTITY_FILTER)               += vf_identity.o
 OBJS-$(CONFIG_IDET_FILTER)                   += vf_idet.o
 OBJS-$(CONFIG_IL_FILTER)                     += vf_il.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 7b71918ed6..ff491ef8e1 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -305,6 +305,7 @@ extern const AVFilter ff_vf_hwmap;
 extern const AVFilter ff_vf_hwupload;
 extern const AVFilter ff_vf_hwupload_cuda;
 extern const AVFilter ff_vf_hysteresis;
+extern const AVFilter ff_vf_iccgen;
 extern const AVFilter ff_vf_identity;
 extern const AVFilter ff_vf_idet;
 extern const AVFilter ff_vf_il;
diff --git a/libavfilter/vf_iccgen.c b/libavfilter/vf_iccgen.c
new file mode 100644
index 0000000000..67d02f5bc2
--- /dev/null
+++ b/libavfilter/vf_iccgen.c
@@ -0,0 +1,181 @@
+/*
+ * Copyright (c) 2022 Niklas Haas
+ * 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
+ * filter for generating ICC profiles
+ */
+
+#include <lcms2.h>
+
+#include "libavutil/opt.h"
+#include "libavutil/pixdesc.h"
+
+#include "avfilter.h"
+#include "fflcms2.h"
+#include "internal.h"
+
+typedef struct IccGenContext {
+    const AVClass *class;
+    FFIccContext icc;
+    /* options */
+    int color_prim;
+    int color_trc;
+    int force;
+    /* (cached) generated ICC profile */
+    cmsHPROFILE profile;
+    int profile_prim;
+    int profile_trc;
+} IccGenContext;
+
+#define OFFSET(x) offsetof(IccGenContext, x)
+#define VF AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption iccgen_options[] = {
+    {"color_primaries", "select color primaries", OFFSET(color_prim), AV_OPT_TYPE_INT, {.i64=0}, 0, AVCOL_PRI_NB-1, VF, "color_primaries"},
+        {"auto",          "infer based on frame",  0, AV_OPT_TYPE_CONST, {.i64=0},                      0, 0, VF, "color_primaries"},
+        {"bt709",                           NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_BT709},        0, 0, VF, "color_primaries"},
+        {"bt470m",                          NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_BT470M},       0, 0, VF, "color_primaries"},
+        {"bt470bg",                         NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_BT470BG},      0, 0, VF, "color_primaries"},
+        {"smpte170m",                       NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_SMPTE170M},    0, 0, VF, "color_primaries"},
+        {"smpte240m",                       NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_SMPTE240M},    0, 0, VF, "color_primaries"},
+        {"film",                            NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_FILM},         0, 0, VF, "color_primaries"},
+        {"bt2020",                          NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_BT2020},       0, 0, VF, "color_primaries"},
+        {"smpte428",                        NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_SMPTE428},     0, 0, VF, "color_primaries"},
+        {"smpte431",                        NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_SMPTE431},     0, 0, VF, "color_primaries"},
+        {"smpte432",                        NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_SMPTE432},     0, 0, VF, "color_primaries"},
+        {"jedec-p22",                       NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_JEDEC_P22},    0, 0, VF, "color_primaries"},
+        {"ebu3213",                         NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_PRI_EBU3213},      0, 0, VF, "color_primaries"},
+    {"color_trc", "select color transfer", OFFSET(color_trc), AV_OPT_TYPE_INT, {.i64=0}, 0, AVCOL_TRC_NB-1, VF, "color_trc"},
+        {"auto",         "infer based on frame",  0, AV_OPT_TYPE_CONST, {.i64=0},                      0, 0, VF, "color_trc"},
+        {"bt709",                          NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_BT709},        0, 0, VF, "color_trc"},
+        {"bt470m",                         NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_GAMMA22},      0, 0, VF, "color_trc"},
+        {"bt470bg",                        NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_GAMMA28},      0, 0, VF, "color_trc"},
+        {"smpte170m",                      NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_SMPTE170M},    0, 0, VF, "color_trc"},
+        {"smpte240m",                      NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_SMPTE240M},    0, 0, VF, "color_trc"},
+        {"linear",                         NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_LINEAR},       0, 0, VF, "color_trc"},
+        {"iec61966-2-4",                   NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_IEC61966_2_4}, 0, 0, VF, "color_trc"},
+        {"bt1361e",                        NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_BT1361_ECG},   0, 0, VF, "color_trc"},
+        {"iec61966-2-1",                   NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_IEC61966_2_1}, 0, 0, VF, "color_trc"},
+        {"bt2020-10",                      NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_BT2020_10},    0, 0, VF, "color_trc"},
+        {"bt2020-12",                      NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_BT2020_12},    0, 0, VF, "color_trc"},
+        {"smpte2084",                      NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_SMPTE2084},    0, 0, VF, "color_trc"},
+        {"arib-std-b67",                   NULL,  0, AV_OPT_TYPE_CONST, {.i64=AVCOL_TRC_ARIB_STD_B67}, 0, 0, VF, "color_trc"},
+    { "force", "overwrite existing ICC profile", OFFSET(force), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, VF },
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(iccgen);
+
+static av_cold void iccgen_uninit(AVFilterContext *avctx)
+{
+    IccGenContext *s = avctx->priv;
+    cmsCloseProfile(s->profile);
+    ff_icc_context_uninit(&s->icc);
+}
+
+static av_cold int iccgen_init(AVFilterContext *avctx)
+{
+    IccGenContext *s = avctx->priv;
+    return ff_icc_context_init(&s->icc, avctx);
+}
+
+static int iccgen_filter_frame(AVFilterLink *inlink, AVFrame *frame)
+{
+    AVFilterContext *avctx = inlink->dst;
+    IccGenContext *s = avctx->priv;
+    enum AVColorTransferCharacteristic trc;
+    enum AVColorPrimaries prim;
+    int ret;
+
+    if (av_frame_get_side_data(frame, AV_FRAME_DATA_ICC_PROFILE)) {
+        if (s->force) {
+            av_frame_remove_side_data(frame, AV_FRAME_DATA_ICC_PROFILE);
+        } else {
+            return ff_filter_frame(inlink->dst->outputs[0], frame);
+        }
+    }
+
+    trc = s->color_trc ? s->color_trc : frame->color_trc;
+    if (trc == AVCOL_TRC_UNSPECIFIED) {
+        const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
+        if (!desc)
+            return AVERROR_INVALIDDATA;
+
+        if ((desc->flags & AV_PIX_FMT_FLAG_RGB) || frame->color_range == AVCOL_RANGE_JPEG) {
+            /* Default to sRGB for RGB or full-range content */
+            trc = AVCOL_TRC_IEC61966_2_1;
+        } else {
+            /* Default to an ITU-R transfer depending on the bit-depth */
+            trc = desc->comp[0].depth >= 12 ? AVCOL_TRC_BT2020_12
+                : desc->comp[0].depth >= 10 ? AVCOL_TRC_BT2020_10
+                : AVCOL_TRC_BT709;
+        }
+    }
+
+    prim = s->color_prim ? s->color_prim : frame->color_primaries;
+    if (prim == AVCOL_PRI_UNSPECIFIED) {
+        /* Simply always default to sRGB/BT.709 primaries to avoid surprises */
+        prim = AVCOL_PRI_BT709;
+    }
+
+    if (s->profile && prim != s->profile_prim && trc != s->profile_trc) {
+        cmsCloseProfile(s->profile);
+        s->profile = NULL;
+    }
+
+    if (!s->profile) {
+        if ((ret = ff_icc_profile_generate(&s->icc, prim, trc, &s->profile)) < 0)
+            return ret;
+        s->profile_prim = prim;
+        s->profile_trc = trc;
+    }
+
+    if ((ret = ff_icc_profile_attach(&s->icc, s->profile, frame)) < 0)
+        return ret;
+
+    return ff_filter_frame(inlink->dst->outputs[0], frame);
+}
+
+static const AVFilterPad iccgen_inputs[] = {
+    {
+        .name           = "default",
+        .type           = AVMEDIA_TYPE_VIDEO,
+        .filter_frame   = iccgen_filter_frame,
+    },
+};
+
+static const AVFilterPad iccgen_outputs[] = {
+    {
+        .name           = "default",
+        .type           = AVMEDIA_TYPE_VIDEO,
+    },
+};
+
+const AVFilter ff_vf_iccgen = {
+    .name        = "iccgen",
+    .description = NULL_IF_CONFIG_SMALL("Generate and attach ICC profiles."),
+    .priv_size   = sizeof(IccGenContext),
+    .priv_class  = &iccgen_class,
+    .flags       = AVFILTER_FLAG_METADATA_ONLY,
+    .init        = &iccgen_init,
+    .uninit      = &iccgen_uninit,
+    FILTER_INPUTS(iccgen_inputs),
+    FILTER_OUTPUTS(iccgen_outputs),
+};