avfilter: add zscale filter

Signed-off-by: Paul B Mahol <onemda@gmail.com>

7 files changed, 915 insertions, 1 deletions

diff --git a/Changelog b/Changelog
index f93a732037..b5be951979 100644
--- a/Changelog
+++ b/Changelog
@@ -21,6 +21,7 @@ version <next>:
 - extensive native AAC encoder improvements
 - ADPCM PSX decoder
 - genh, vag, ads & svag demuxer
+- zscale filter
 
 
 version 2.8:
diff --git a/configure b/configure
index 2368d73465..1bbaf7f1f0 100755
--- a/configure
+++ b/configure
@@ -269,6 +269,7 @@ External library support:
   --enable-libxcb-shape    enable X11 grabbing shape rendering [autodetect]
   --enable-libxvid         enable Xvid encoding via xvidcore,
                            native MPEG-4/Xvid encoder exists [no]
+  --enable-libzimg         enable z.lib, needed for zscale filter [no]
   --enable-libzmq          enable message passing via libzmq [no]
   --enable-libzvbi         enable teletext support via libzvbi [no]
   --disable-lzma           disable lzma [autodetect]
@@ -1456,6 +1457,7 @@ EXTERNAL_LIBRARY_LIST="
     libxcb_shape
     libxcb_xfixes
     libxvid
+    libzimg
     libzmq
     libzvbi
     lzma
@@ -2843,6 +2845,7 @@ tinterlace_pad_test_deps="tinterlace_filter"
 uspp_filter_deps="gpl avcodec"
 zmq_filter_deps="libzmq"
 zoompan_filter_deps="swscale"
+zscale_filter_deps="libzimg"
 
 # examples
 avio_reading="avformat avcodec avutil"
@@ -5423,6 +5426,7 @@ enabled libx265           && require_pkg_config x265 x265.h x265_api_get &&
                                die "ERROR: libx265 version must be >= 57."; }
 enabled libxavs           && require libxavs xavs.h xavs_encoder_encode -lxavs
 enabled libxvid           && require libxvid xvid.h xvid_global -lxvidcore
+enabled libzimg           && require_pkg_config zimg zimg.h zimg_get_api_version
 enabled libzmq            && require_pkg_config libzmq zmq.h zmq_ctx_new
 enabled libzvbi           && require libzvbi libzvbi.h vbi_decoder_new -lzvbi
 enabled mmal              && { check_lib interface/mmal/mmal.h mmal_port_connect -lmmal_core -lmmal_util -lmmal_vc_client -lbcm_host ||
diff --git a/doc/filters.texi b/doc/filters.texi
index f58f01418c..1af0a72f24 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -11856,6 +11856,177 @@ zoompan=z='min(zoom+0.0015,1.5)':d=700:x='iw/2-(iw/zoom/2)':y='ih/2-(ih/zoom/2)'
 @end example
 @end itemize
 
+@section zscale
+Scale (resize) the input video, using the z.lib library:
+https://github.com/sekrit-twc/zimg.
+
+The zscale filter forces the output display aspect ratio to be the same
+as the input, by changing the output sample aspect ratio.
+
+If the input image format is different from the format requested by
+the next filter, the zscale filter will convert the input to the
+requested format.
+
+@subsection Options
+The filter accepts the following options.
+
+@table @option
+@item width, w
+@item height, h
+Set the output video dimension expression. Default value is the input
+dimension.
+
+If the @var{width} or @var{w} is 0, the input width is used for the output.
+If the @var{height} or @var{h} is 0, the input height is used for the output.
+
+If one of the values is -1, the zscale filter will use a value that
+maintains the aspect ratio of the input image, calculated from the
+other specified dimension. If both of them are -1, the input size is
+used
+
+If one of the values is -n with n > 1, the zscale filter will also use a value
+that maintains the aspect ratio of the input image, calculated from the other
+specified dimension. After that it will, however, make sure that the calculated
+dimension is divisible by n and adjust the value if necessary.
+
+See below for the list of accepted constants for use in the dimension
+expression.
+
+@item size, s
+Set the video size. For the syntax of this option, check the
+@ref{video size syntax,,"Video size" section in the ffmpeg-utils manual,ffmpeg-utils}.
+
+@item dither, d
+Set the dither type.
+
+Possible values are:
+@table @var
+@item none
+@item ordered
+@item random
+@item error_diffusion
+@end table
+
+Default is none.
+
+@item filter, f
+Set the resize filter type.
+
+Possible values are:
+@table @var
+@item point
+@item bilinear
+@item bicubic
+@item spline16
+@item spline36
+@item lanczos
+@end table
+
+Default is bilinear.
+
+@item range, r
+Set the color range.
+
+Possible values are:
+@table @var
+@item input
+@item limited
+@item full
+@end table
+
+Default is same as input.
+
+@item primaries, p
+Set the color primaries.
+
+Possible values are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 170m
+@item 240m
+@item 2020
+@end table
+
+Default is same as input.
+
+@item transfer, t
+Set the transfer characteristics.
+
+Possible values are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 601
+@item linear
+@item 2020_10
+@item 2020_12
+@end table
+
+Default is same as input.
+
+@item matrix, m
+Set the colorspace matrix.
+
+Possible value are:
+@table @var
+@item input
+@item 709
+@item unspecified
+@item 470bg
+@item 170m
+@item 2020_ncl
+@item 2020_cl
+@end table
+
+Default is same as input.
+@end table
+
+The values of the @option{w} and @option{h} options are expressions
+containing the following constants:
+
+@table @var
+@item in_w
+@item in_h
+The input width and height
+
+@item iw
+@item ih
+These are the same as @var{in_w} and @var{in_h}.
+
+@item out_w
+@item out_h
+The output (scaled) width and height
+
+@item ow
+@item oh
+These are the same as @var{out_w} and @var{out_h}
+
+@item a
+The same as @var{iw} / @var{ih}
+
+@item sar
+input sample aspect ratio
+
+@item dar
+The input display aspect ratio. Calculated from @code{(iw / ih) * sar}.
+
+@item hsub
+@item vsub
+horizontal and vertical input chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+
+@item ohsub
+@item ovsub
+horizontal and vertical output chroma subsample values. For example for the
+pixel format "yuv422p" @var{hsub} is 2 and @var{vsub} is 1.
+@end table
+
+@table @option
+@end table
+
 @c man end VIDEO FILTERS
 
 @chapter Video Sources
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 69766dae7c..a095a1095b 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -246,6 +246,7 @@ OBJS-$(CONFIG_XBR_FILTER)                    += vf_xbr.o
 OBJS-$(CONFIG_YADIF_FILTER)                  += vf_yadif.o
 OBJS-$(CONFIG_ZMQ_FILTER)                    += f_zmq.o
 OBJS-$(CONFIG_ZOOMPAN_FILTER)                += vf_zoompan.o
+OBJS-$(CONFIG_ZSCALE_FILTER)                 += vf_zscale.o
 
 OBJS-$(CONFIG_ALLRGB_FILTER)                 += vsrc_testsrc.o
 OBJS-$(CONFIG_ALLYUV_FILTER)                 += vsrc_testsrc.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 6c4ddf1a18..3ab9a487e4 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -267,6 +267,7 @@ void avfilter_register_all(void)
     REGISTER_FILTER(YADIF,          yadif,          vf);
     REGISTER_FILTER(ZMQ,            zmq,            vf);
     REGISTER_FILTER(ZOOMPAN,        zoompan,        vf);
+    REGISTER_FILTER(ZSCALE,         zscale,         vf);
 
     REGISTER_FILTER(ALLRGB,         allrgb,         vsrc);
     REGISTER_FILTER(ALLYUV,         allyuv,         vsrc);
diff --git a/libavfilter/version.h b/libavfilter/version.h
index 0964baf360..4a24484d83 100644
--- a/libavfilter/version.h
+++ b/libavfilter/version.h
@@ -30,7 +30,7 @@
 #include "libavutil/version.h"
 
 #define LIBAVFILTER_VERSION_MAJOR   6
-#define LIBAVFILTER_VERSION_MINOR  11
+#define LIBAVFILTER_VERSION_MINOR  12
 #define LIBAVFILTER_VERSION_MICRO 100
 
 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vf_zscale.c b/libavfilter/vf_zscale.c
new file mode 100644
index 0000000000..50cac77d1f
--- /dev/null
+++ b/libavfilter/vf_zscale.c
@@ -0,0 +1,736 @@
+/*
+ * Copyright (c) 2015 Paul B Mahol
+ *
+ * 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
+ * zscale video filter using z.lib library
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include <zimg.h>
+
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+#include "libavutil/avstring.h"
+#include "libavutil/eval.h"
+#include "libavutil/internal.h"
+#include "libavutil/mathematics.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/avassert.h"
+
+static const char *const var_names[] = {
+    "in_w",   "iw",
+    "in_h",   "ih",
+    "out_w",  "ow",
+    "out_h",  "oh",
+    "a",
+    "sar",
+    "dar",
+    "hsub",
+    "vsub",
+    "ohsub",
+    "ovsub",
+    NULL
+};
+
+enum var_name {
+    VAR_IN_W,   VAR_IW,
+    VAR_IN_H,   VAR_IH,
+    VAR_OUT_W,  VAR_OW,
+    VAR_OUT_H,  VAR_OH,
+    VAR_A,
+    VAR_SAR,
+    VAR_DAR,
+    VAR_HSUB,
+    VAR_VSUB,
+    VAR_OHSUB,
+    VAR_OVSUB,
+    VARS_NB
+};
+
+typedef struct ZScaleContext {
+    const AVClass *class;
+
+    /**
+     * New dimensions. Special values are:
+     *   0 = original width/height
+     *  -1 = keep original aspect
+     *  -N = try to keep aspect but make sure it is divisible by N
+     */
+    int w, h;
+    int dither;
+    int filter;
+    int colorspace;
+    int trc;
+    int primaries;
+    int range;
+    char *size_str;
+
+    char *w_expr;               ///< width  expression string
+    char *h_expr;               ///< height expression string
+
+    int out_h_chr_pos;
+    int out_v_chr_pos;
+    int in_h_chr_pos;
+    int in_v_chr_pos;
+
+    int force_original_aspect_ratio;
+
+    void *tmp;
+    size_t tmp_size;
+
+    zimg_image_format src_format, dst_format;
+    zimg_image_format alpha_src_format, alpha_dst_format;
+    zimg_graph_builder_params alpha_params, params;
+    zimg_filter_graph *alpha_graph, *graph;
+
+    enum AVColorSpace in_colorspace, out_colorspace;
+    enum AVColorTransferCharacteristic in_trc, out_trc;
+    enum AVColorPrimaries in_primaries, out_primaries;
+    enum AVColorRange in_range, out_range;
+} ZScaleContext;
+
+static av_cold int init_dict(AVFilterContext *ctx, AVDictionary **opts)
+{
+    ZScaleContext *s = ctx->priv;
+    int ret;
+
+    if (s->size_str && (s->w_expr || s->h_expr)) {
+        av_log(ctx, AV_LOG_ERROR,
+               "Size and width/height expressions cannot be set at the same time.\n");
+            return AVERROR(EINVAL);
+    }
+
+    if (s->w_expr && !s->h_expr)
+        FFSWAP(char *, s->w_expr, s->size_str);
+
+    if (s->size_str) {
+        char buf[32];
+        if ((ret = av_parse_video_size(&s->w, &s->h, s->size_str)) < 0) {
+            av_log(ctx, AV_LOG_ERROR,
+                   "Invalid size '%s'\n", s->size_str);
+            return ret;
+        }
+        snprintf(buf, sizeof(buf)-1, "%d", s->w);
+        av_opt_set(s, "w", buf, 0);
+        snprintf(buf, sizeof(buf)-1, "%d", s->h);
+        av_opt_set(s, "h", buf, 0);
+    }
+    if (!s->w_expr)
+        av_opt_set(s, "w", "iw", 0);
+    if (!s->h_expr)
+        av_opt_set(s, "h", "ih", 0);
+
+    return 0;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pixel_fmts[] = {
+        AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
+        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
+        AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
+        AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
+        AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ444P,
+        AV_PIX_FMT_YUVJ411P,
+        AV_PIX_FMT_YUV420P9, AV_PIX_FMT_YUV422P9, AV_PIX_FMT_YUV444P9,
+        AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
+        AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12,
+        AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
+        AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
+        AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
+        AV_PIX_FMT_YUVA420P9, AV_PIX_FMT_YUVA422P9, AV_PIX_FMT_YUVA444P9,
+        AV_PIX_FMT_YUVA420P10, AV_PIX_FMT_YUVA422P10, AV_PIX_FMT_YUVA444P10,
+        AV_PIX_FMT_YUVA420P16, AV_PIX_FMT_YUVA422P16, AV_PIX_FMT_YUVA444P16,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRP9, AV_PIX_FMT_GBRP10,
+        AV_PIX_FMT_GBRP12, AV_PIX_FMT_GBRP14, AV_PIX_FMT_GBRP16,
+        AV_PIX_FMT_GBRAP, AV_PIX_FMT_GBRAP16,
+        AV_PIX_FMT_NONE
+    };
+    int ret;
+
+    ret = ff_formats_ref(ff_make_format_list(pixel_fmts), &ctx->inputs[0]->out_formats);
+    if (ret < 0)
+        return ret;
+    return ff_formats_ref(ff_make_format_list(pixel_fmts), &ctx->outputs[0]->in_formats);
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    AVFilterLink *inlink = outlink->src->inputs[0];
+    ZScaleContext *s = ctx->priv;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+    const AVPixFmtDescriptor *out_desc = av_pix_fmt_desc_get(outlink->format);
+    int64_t w, h;
+    double var_values[VARS_NB], res;
+    char *expr;
+    int ret;
+    int factor_w, factor_h;
+
+    var_values[VAR_IN_W]  = var_values[VAR_IW] = inlink->w;
+    var_values[VAR_IN_H]  = var_values[VAR_IH] = inlink->h;
+    var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
+    var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
+    var_values[VAR_A]     = (double) inlink->w / inlink->h;
+    var_values[VAR_SAR]   = inlink->sample_aspect_ratio.num ?
+        (double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
+    var_values[VAR_DAR]   = var_values[VAR_A] * var_values[VAR_SAR];
+    var_values[VAR_HSUB]  = 1 << desc->log2_chroma_w;
+    var_values[VAR_VSUB]  = 1 << desc->log2_chroma_h;
+    var_values[VAR_OHSUB] = 1 << out_desc->log2_chroma_w;
+    var_values[VAR_OVSUB] = 1 << out_desc->log2_chroma_h;
+
+    /* evaluate width and height */
+    av_expr_parse_and_eval(&res, (expr = s->w_expr),
+                           var_names, var_values,
+                           NULL, NULL, NULL, NULL, NULL, 0, ctx);
+    s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
+    if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
+                                      var_names, var_values,
+                                      NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+        goto fail;
+    s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
+    /* evaluate again the width, as it may depend on the output height */
+    if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
+                                      var_names, var_values,
+                                      NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+        goto fail;
+    s->w = res;
+
+    w = s->w;
+    h = s->h;
+
+    /* Check if it is requested that the result has to be divisible by a some
+     * factor (w or h = -n with n being the factor). */
+    factor_w = 1;
+    factor_h = 1;
+    if (w < -1) {
+        factor_w = -w;
+    }
+    if (h < -1) {
+        factor_h = -h;
+    }
+
+    if (w < 0 && h < 0)
+        s->w = s->h = 0;
+
+    if (!(w = s->w))
+        w = inlink->w;
+    if (!(h = s->h))
+        h = inlink->h;
+
+    /* Make sure that the result is divisible by the factor we determined
+     * earlier. If no factor was set, it is nothing will happen as the default
+     * factor is 1 */
+    if (w < 0)
+        w = av_rescale(h, inlink->w, inlink->h * factor_w) * factor_w;
+    if (h < 0)
+        h = av_rescale(w, inlink->h, inlink->w * factor_h) * factor_h;
+
+    /* Note that force_original_aspect_ratio may overwrite the previous set
+     * dimensions so that it is not divisible by the set factors anymore. */
+    if (s->force_original_aspect_ratio) {
+        int tmp_w = av_rescale(h, inlink->w, inlink->h);
+        int tmp_h = av_rescale(w, inlink->h, inlink->w);
+
+        if (s->force_original_aspect_ratio == 1) {
+             w = FFMIN(tmp_w, w);
+             h = FFMIN(tmp_h, h);
+        } else {
+             w = FFMAX(tmp_w, w);
+             h = FFMAX(tmp_h, h);
+        }
+    }
+
+    if (w > INT_MAX || h > INT_MAX ||
+        (h * inlink->w) > INT_MAX  ||
+        (w * inlink->h) > INT_MAX)
+        av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
+
+    outlink->w = w;
+    outlink->h = h;
+
+    if (inlink->w == outlink->w &&
+        inlink->h == outlink->h &&
+        inlink->format == outlink->format)
+        ;
+    else {
+    }
+
+    if (inlink->sample_aspect_ratio.num){
+        outlink->sample_aspect_ratio = av_mul_q((AVRational){outlink->h * inlink->w, outlink->w * inlink->h}, inlink->sample_aspect_ratio);
+    } else
+        outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
+
+    av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d fmt:%s sar:%d/%d -> w:%d h:%d fmt:%s sar:%d/%d\n",
+           inlink ->w, inlink ->h, av_get_pix_fmt_name( inlink->format),
+           inlink->sample_aspect_ratio.num, inlink->sample_aspect_ratio.den,
+           outlink->w, outlink->h, av_get_pix_fmt_name(outlink->format),
+           outlink->sample_aspect_ratio.num, outlink->sample_aspect_ratio.den);
+    return 0;
+
+fail:
+    av_log(ctx, AV_LOG_ERROR,
+           "Error when evaluating the expression '%s'.\n"
+           "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
+           expr, s->w_expr, s->h_expr);
+    return ret;
+}
+
+static int print_zimg_error(AVFilterContext *ctx)
+{
+    char err_msg[1024];
+    int err_code = zimg_get_last_error(err_msg, sizeof(err_msg));
+
+    av_log(ctx, AV_LOG_ERROR, "code %d: %s\n", err_code, err_msg);
+
+    return err_code;
+}
+
+static int convert_matrix(enum AVColorSpace colorspace)
+{
+    switch (colorspace) {
+    case AVCOL_SPC_RGB:
+        return ZIMG_MATRIX_RGB;
+    case AVCOL_SPC_BT709:
+        return ZIMG_MATRIX_709;
+    case AVCOL_SPC_UNSPECIFIED:
+        return ZIMG_MATRIX_UNSPECIFIED;
+    case AVCOL_SPC_BT470BG:
+        return ZIMG_MATRIX_470BG;
+    case AVCOL_SPC_SMPTE170M:
+        return ZIMG_MATRIX_170M;
+    case AVCOL_SPC_YCGCO:
+        return ZIMG_MATRIX_YCGCO;
+    case AVCOL_SPC_BT2020_NCL:
+        return ZIMG_MATRIX_2020_NCL;
+    case AVCOL_SPC_BT2020_CL:
+        return ZIMG_MATRIX_2020_CL;
+    }
+    return ZIMG_MATRIX_UNSPECIFIED;
+}
+
+static int convert_trc(enum AVColorTransferCharacteristic color_trc)
+{
+    switch (color_trc) {
+    case AVCOL_TRC_UNSPECIFIED:
+        return ZIMG_TRANSFER_UNSPECIFIED;
+    case AVCOL_TRC_BT709:
+        return ZIMG_TRANSFER_709;
+    case AVCOL_TRC_SMPTE170M:
+        return ZIMG_TRANSFER_601;
+    case AVCOL_TRC_LINEAR:
+        return ZIMG_TRANSFER_LINEAR;
+    case AVCOL_TRC_BT2020_10:
+        return ZIMG_TRANSFER_2020_10;
+    case AVCOL_TRC_BT2020_12:
+        return ZIMG_TRANSFER_2020_12;
+    }
+    return ZIMG_TRANSFER_UNSPECIFIED;
+}
+
+static int convert_primaries(enum AVColorPrimaries color_primaries)
+{
+    switch (color_primaries) {
+    case AVCOL_PRI_UNSPECIFIED:
+        return ZIMG_PRIMARIES_UNSPECIFIED;
+    case AVCOL_PRI_BT709:
+        return ZIMG_PRIMARIES_709;
+    case AVCOL_PRI_SMPTE170M:
+        return ZIMG_PRIMARIES_170M;
+    case AVCOL_PRI_SMPTE240M:
+        return ZIMG_PRIMARIES_240M;
+    case AVCOL_PRI_BT2020:
+        return ZIMG_PRIMARIES_2020;
+    }
+    return ZIMG_PRIMARIES_UNSPECIFIED;
+}
+
+static int convert_range(enum AVColorRange color_range)
+{
+    switch (color_range) {
+    case AVCOL_RANGE_UNSPECIFIED:
+    case AVCOL_RANGE_MPEG:
+        return ZIMG_RANGE_LIMITED;
+    case AVCOL_RANGE_JPEG:
+        return ZIMG_RANGE_FULL;
+    }
+    return ZIMG_RANGE_LIMITED;
+}
+
+static int filter_frame(AVFilterLink *link, AVFrame *in)
+{
+    ZScaleContext *s = link->dst->priv;
+    AVFilterLink *outlink = link->dst->outputs[0];
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
+    const AVPixFmtDescriptor *odesc = av_pix_fmt_desc_get(outlink->format);
+    zimg_image_buffer_const src_buf = { ZIMG_API_VERSION };
+    zimg_image_buffer dst_buf = { ZIMG_API_VERSION };
+    char buf[32];
+    size_t tmp_size;
+    int ret = 0, plane;
+    AVFrame *out;
+
+    out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+    if (!out) {
+        av_frame_free(&in);
+        return AVERROR(ENOMEM);
+    }
+
+    av_frame_copy_props(out, in);
+    out->width  = outlink->w;
+    out->height = outlink->h;
+
+    if(   in->width  != link->w
+       || in->height != link->h
+       || in->format != link->format
+       || s->in_colorspace != in->colorspace
+       || s->in_trc  != in->color_trc
+       || s->in_primaries != in->color_primaries
+       || s->in_range != in->color_range
+       || s->out_colorspace != out->colorspace
+       || s->out_trc  != out->color_trc
+       || s->out_primaries != out->color_primaries
+       || s->out_range != out->color_range) {
+        snprintf(buf, sizeof(buf)-1, "%d", outlink->w);
+        av_opt_set(s, "w", buf, 0);
+        snprintf(buf, sizeof(buf)-1, "%d", outlink->h);
+        av_opt_set(s, "h", buf, 0);
+
+        link->dst->inputs[0]->format = in->format;
+        link->dst->inputs[0]->w      = in->width;
+        link->dst->inputs[0]->h      = in->height;
+
+        if ((ret = config_props(outlink)) < 0) {
+            av_frame_free(&in);
+            av_frame_free(&out);
+            return ret;
+        }
+
+        zimg_image_format_default(&s->src_format, ZIMG_API_VERSION);
+        zimg_image_format_default(&s->dst_format, ZIMG_API_VERSION);
+        zimg_graph_builder_params_default(&s->params, ZIMG_API_VERSION);
+
+        s->params.dither_type = s->dither;
+        s->params.cpu_type = ZIMG_CPU_AUTO;
+        s->params.resample_filter = s->filter;
+        s->params.resample_filter_uv = s->filter;
+
+        s->src_format.width = in->width;
+        s->src_format.height = in->height;
+        s->src_format.subsample_w = desc->log2_chroma_w;
+        s->src_format.subsample_h = desc->log2_chroma_h;
+        s->src_format.depth = desc->comp[0].depth;
+        s->src_format.pixel_type = desc->comp[0].depth > 8 ? ZIMG_PIXEL_WORD : ZIMG_PIXEL_BYTE;
+        s->src_format.color_family = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_COLOR_RGB : ZIMG_COLOR_YUV;
+        s->src_format.matrix_coefficients = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_MATRIX_RGB : convert_matrix(in->colorspace);
+        s->src_format.transfer_characteristics = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_TRANSFER_UNSPECIFIED : convert_trc(in->color_trc);
+        s->src_format.color_primaries = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_PRIMARIES_UNSPECIFIED : convert_primaries(in->color_primaries);
+        s->src_format.pixel_range = (desc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_RANGE_FULL : convert_range(in->color_range);
+
+        s->dst_format.width = out->width;
+        s->dst_format.height = out->height;
+        s->dst_format.subsample_w = odesc->log2_chroma_w;
+        s->dst_format.subsample_h = odesc->log2_chroma_h;
+        s->dst_format.depth = odesc->comp[0].depth;
+        s->dst_format.pixel_type = odesc->comp[0].depth > 8 ? ZIMG_PIXEL_WORD : ZIMG_PIXEL_BYTE;
+        s->dst_format.color_family = (odesc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_COLOR_RGB : ZIMG_COLOR_YUV;
+        s->dst_format.matrix_coefficients = (odesc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_MATRIX_RGB : s->colorspace == -1 ? convert_matrix(out->colorspace) : s->colorspace;
+        s->dst_format.transfer_characteristics = (odesc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_TRANSFER_UNSPECIFIED : s->trc == -1 ? convert_trc(out->color_trc) : s->trc;
+        s->dst_format.color_primaries = (odesc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_PRIMARIES_UNSPECIFIED : s->primaries == -1 ? convert_primaries(out->color_primaries) : s->primaries;
+        s->dst_format.pixel_range = (odesc->flags & AV_PIX_FMT_FLAG_RGB) ? ZIMG_RANGE_FULL : s->range == -1 ? convert_range(out->color_range) : s->range;
+
+        if (s->colorspace != -1)
+            out->colorspace = (int)s->dst_format.matrix_coefficients;
+
+        if (s->primaries != -1)
+            out->color_primaries = (int)s->dst_format.color_primaries;
+
+        if (s->range != -1)
+            out->color_range = (int)s->dst_format.pixel_range + 1;
+
+        if (s->trc != -1)
+            out->color_trc = (int)s->dst_format.transfer_characteristics;
+
+        zimg_filter_graph_free(s->graph);
+        s->graph = zimg_filter_graph_build(&s->src_format, &s->dst_format, &s->params);
+        if (!s->graph) {
+            ret = print_zimg_error(link->dst);
+            goto fail;
+        }
+
+        if ((ret = zimg_filter_graph_get_tmp_size(s->graph, &tmp_size))) {
+            ret = print_zimg_error(link->dst);
+            goto fail;
+        }
+
+        if (tmp_size > s->tmp_size) {
+            av_freep(&s->tmp);
+            s->tmp = av_malloc(tmp_size);
+            if (!s->tmp) {
+                ret = AVERROR(ENOMEM);
+                goto fail;
+            }
+            s->tmp_size = tmp_size;
+        }
+
+        s->in_colorspace  = in->colorspace;
+        s->in_trc         = in->color_trc;
+        s->in_primaries   = in->color_primaries;
+        s->in_range       = in->color_range;
+        s->out_colorspace = out->colorspace;
+        s->out_trc        = out->color_trc;
+        s->out_primaries  = out->color_primaries;
+        s->out_range      = out->color_range;
+
+        if (desc->flags & AV_PIX_FMT_FLAG_ALPHA && odesc->flags & AV_PIX_FMT_FLAG_ALPHA) {
+            zimg_image_format_default(&s->alpha_src_format, ZIMG_API_VERSION);
+            zimg_image_format_default(&s->alpha_dst_format, ZIMG_API_VERSION);
+            zimg_graph_builder_params_default(&s->alpha_params, ZIMG_API_VERSION);
+
+            s->alpha_params.dither_type = s->dither;
+            s->alpha_params.cpu_type = ZIMG_CPU_AUTO;
+            s->alpha_params.resample_filter = s->filter;
+
+            s->alpha_src_format.width = in->width;
+            s->alpha_src_format.height = in->height;
+            s->alpha_src_format.depth = desc->comp[0].depth;
+            s->alpha_src_format.pixel_type = desc->comp[0].depth > 8 ? ZIMG_PIXEL_WORD : ZIMG_PIXEL_BYTE;
+            s->alpha_src_format.color_family = ZIMG_COLOR_GREY;
+
+            s->alpha_dst_format.width = out->width;
+            s->alpha_dst_format.height = out->height;
+            s->alpha_dst_format.depth = odesc->comp[0].depth;
+            s->alpha_dst_format.pixel_type = odesc->comp[0].depth > 8 ? ZIMG_PIXEL_WORD : ZIMG_PIXEL_BYTE;
+            s->alpha_dst_format.color_family = ZIMG_COLOR_GREY;
+
+            zimg_filter_graph_free(s->alpha_graph);
+            s->alpha_graph = zimg_filter_graph_build(&s->alpha_src_format, &s->alpha_dst_format, &s->alpha_params);
+            if (!s->alpha_graph) {
+                ret = print_zimg_error(link->dst);
+                goto fail;
+            }
+        }
+    }
+
+    if (s->colorspace != -1)
+        out->colorspace = (int)s->dst_format.matrix_coefficients;
+
+    if (s->primaries != -1)
+        out->color_primaries = (int)s->dst_format.color_primaries;
+
+    if (s->range != -1)
+        out->color_range = (int)s->dst_format.pixel_range;
+
+    if (s->trc != -1)
+        out->color_trc = (int)s->dst_format.transfer_characteristics;
+
+    av_reduce(&out->sample_aspect_ratio.num, &out->sample_aspect_ratio.den,
+              (int64_t)in->sample_aspect_ratio.num * outlink->h * link->w,
+              (int64_t)in->sample_aspect_ratio.den * outlink->w * link->h,
+              INT_MAX);
+
+    for (plane = 0; plane < 3; plane++) {
+        int p = desc->comp[plane].plane;
+        src_buf.plane[plane].data   = in->data[p];
+        src_buf.plane[plane].stride = in->linesize[p];
+        src_buf.plane[plane].mask   = -1;
+
+        p = odesc->comp[plane].plane;
+        dst_buf.plane[plane].data   = out->data[p];
+        dst_buf.plane[plane].stride = out->linesize[p];
+        dst_buf.plane[plane].mask   = -1;
+    }
+
+    ret = zimg_filter_graph_process(s->graph, &src_buf, &dst_buf, s->tmp, 0, 0, 0, 0);
+    if (ret) {
+        print_zimg_error(link->dst);
+        goto fail;
+    }
+
+    if (desc->flags & AV_PIX_FMT_FLAG_ALPHA && odesc->flags & AV_PIX_FMT_FLAG_ALPHA) {
+        src_buf.plane[0].data   = in->data[3];
+        src_buf.plane[0].stride = in->linesize[3];
+        src_buf.plane[0].mask   = -1;
+
+        dst_buf.plane[0].data   = out->data[3];
+        dst_buf.plane[0].stride = out->linesize[3];
+        dst_buf.plane[0].mask   = -1;
+
+        ret = zimg_filter_graph_process(s->alpha_graph, &src_buf, &dst_buf, s->tmp, 0, 0, 0, 0);
+        if (ret) {
+            print_zimg_error(link->dst);
+            goto fail;
+        }
+    } else if (odesc->flags & AV_PIX_FMT_FLAG_ALPHA) {
+        int y;
+
+        for (y = 0; y < outlink->h; y++)
+            memset(out->data[3] + y * out->linesize[3], 0xff, outlink->w);
+    }
+
+fail:
+    av_frame_free(&in);
+    if (ret) {
+        av_frame_free(&out);
+        return ret;
+    }
+
+    return ff_filter_frame(outlink, out);
+}
+
+static void uninit(AVFilterContext *ctx)
+{
+    ZScaleContext *s = ctx->priv;
+
+    zimg_filter_graph_free(s->graph);
+    av_freep(&s->tmp);
+    s->tmp_size = 0;
+}
+
+static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
+                           char *res, int res_len, int flags)
+{
+    ZScaleContext *s = ctx->priv;
+    int ret;
+
+    if (   !strcmp(cmd, "width")  || !strcmp(cmd, "w")
+        || !strcmp(cmd, "height") || !strcmp(cmd, "h")) {
+
+        int old_w = s->w;
+        int old_h = s->h;
+        AVFilterLink *outlink = ctx->outputs[0];
+
+        av_opt_set(s, cmd, args, 0);
+        if ((ret = config_props(outlink)) < 0) {
+            s->w = old_w;
+            s->h = old_h;
+        }
+    } else
+        ret = AVERROR(ENOSYS);
+
+    return ret;
+}
+
+#define OFFSET(x) offsetof(ZScaleContext, x)
+#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
+
+static const AVOption zscale_options[] = {
+    { "w",      "Output video width",  OFFSET(w_expr),    AV_OPT_TYPE_STRING, .flags = FLAGS },
+    { "width",  "Output video width",  OFFSET(w_expr),    AV_OPT_TYPE_STRING, .flags = FLAGS },
+    { "h",      "Output video height", OFFSET(h_expr),    AV_OPT_TYPE_STRING, .flags = FLAGS },
+    { "height", "Output video height", OFFSET(h_expr),    AV_OPT_TYPE_STRING, .flags = FLAGS },
+    { "size",   "set video size",      OFFSET(size_str),  AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { "s",      "set video size",      OFFSET(size_str),  AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, FLAGS },
+    { "dither", "set dither type",     OFFSET(dither),    AV_OPT_TYPE_INT, {.i64 = 0}, 0, ZIMG_DITHER_ERROR_DIFFUSION, FLAGS, "dither" },
+    { "d",      "set dither type",     OFFSET(dither),    AV_OPT_TYPE_INT, {.i64 = 0}, 0, ZIMG_DITHER_ERROR_DIFFUSION, FLAGS, "dither" },
+    {     "none",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_DITHER_NONE},     0, 0, FLAGS, "dither" },
+    {     "ordered",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_DITHER_ORDERED},  0, 0, FLAGS, "dither" },
+    {     "random",           0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_DITHER_RANDOM},   0, 0, FLAGS, "dither" },
+    {     "error_diffusion",  0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_DITHER_ERROR_DIFFUSION}, 0, 0, FLAGS, "dither" },
+    { "filter", "set filter type",     OFFSET(filter),    AV_OPT_TYPE_INT, {.i64 = ZIMG_RESIZE_BILINEAR}, 0, ZIMG_RESIZE_LANCZOS, FLAGS, "filter" },
+    { "f",      "set filter type",     OFFSET(filter),    AV_OPT_TYPE_INT, {.i64 = ZIMG_RESIZE_BILINEAR}, 0, ZIMG_RESIZE_LANCZOS, FLAGS, "filter" },
+    {     "point",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_POINT},    0, 0, FLAGS, "filter" },
+    {     "bilinear",         0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_BILINEAR}, 0, 0, FLAGS, "filter" },
+    {     "bicubic",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_BICUBIC},  0, 0, FLAGS, "filter" },
+    {     "spline16",         0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_SPLINE16}, 0, 0, FLAGS, "filter" },
+    {     "splite36",         0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_SPLINE36}, 0, 0, FLAGS, "filter" },
+    {     "lanczos",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RESIZE_LANCZOS},  0, 0, FLAGS, "filter" },
+    { "range", "set color range",      OFFSET(range),     AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_RANGE_FULL, FLAGS, "range" },
+    { "r",     "set color range",      OFFSET(range),     AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_RANGE_FULL, FLAGS, "range" },
+    {     "input",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = -1},                 0, 0, FLAGS, "range" },
+    {     "limited",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RANGE_LIMITED}, 0, 0, FLAGS, "range" },
+    {     "full",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_RANGE_FULL},    0, 0, FLAGS, "range" },
+    { "primaries", "set color primaries", OFFSET(primaries), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_PRIMARIES_2020, FLAGS, "primaries" },
+    { "p",         "set color primaries", OFFSET(primaries), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_PRIMARIES_2020, FLAGS, "primaries" },
+    {     "input",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = -1},                         0, 0, FLAGS, "primaries" },
+    {     "709",              0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_PRIMARIES_709},         0, 0, FLAGS, "primaries" },
+    {     "unspecified",      0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_PRIMARIES_UNSPECIFIED}, 0, 0, FLAGS, "primaries" },
+    {     "170m",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_PRIMARIES_170M},        0, 0, FLAGS, "primaries" },
+    {     "240m",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_PRIMARIES_240M},        0, 0, FLAGS, "primaries" },
+    {     "2020",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_PRIMARIES_2020},        0, 0, FLAGS, "primaries" },
+    { "transfer", "set transfer characteristic", OFFSET(trc), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_TRANSFER_2020_12, FLAGS, "transfer" },
+    { "t",        "set transfer characteristic", OFFSET(trc), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_TRANSFER_2020_12, FLAGS, "transfer" },
+    {     "input",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = -1},                         0, 0, FLAGS, "transfer" },
+    {     "709",              0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_709},         0, 0, FLAGS, "transfer" },
+    {     "unspecified",      0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_UNSPECIFIED}, 0, 0, FLAGS, "transfer" },
+    {     "601",              0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_601},         0, 0, FLAGS, "transfer" },
+    {     "linear",           0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_LINEAR},      0, 0, FLAGS, "transfer" },
+    {     "2020_10",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_2020_10},     0, 0, FLAGS, "transfer" },
+    {     "2020_12",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_TRANSFER_2020_12},     0, 0, FLAGS, "transfer" },
+    { "matrix", "set colorspace matrix", OFFSET(colorspace), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_MATRIX_2020_CL, FLAGS, "matrix" },
+    { "m",      "set colorspace matrix", OFFSET(colorspace), AV_OPT_TYPE_INT, {.i64 = -1}, -1, ZIMG_MATRIX_2020_CL, FLAGS, "matrix" },
+    {     "input",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = -1},                      0, 0, FLAGS, "matrix" },
+    {     "709",              0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_709},         0, 0, FLAGS, "matrix" },
+    {     "unspecified",      0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_UNSPECIFIED}, 0, 0, FLAGS, "matrix" },
+    {     "470bg",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_470BG},       0, 0, FLAGS, "matrix" },
+    {     "170m",             0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_170M},        0, 0, FLAGS, "matrix" },
+    {     "ycgco",            0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_YCGCO},       0, 0, FLAGS, "matrix" },
+    {     "2020_ncl",         0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_2020_NCL},    0, 0, FLAGS, "matrix" },
+    {     "2020_cl",          0,       0,                 AV_OPT_TYPE_CONST, {.i64 = ZIMG_MATRIX_2020_CL},     0, 0, FLAGS, "matrix" },
+    { NULL }
+};
+
+static const AVClass zscale_class = {
+    .class_name       = "zscale",
+    .item_name        = av_default_item_name,
+    .option           = zscale_options,
+    .version          = LIBAVUTIL_VERSION_INT,
+    .category         = AV_CLASS_CATEGORY_FILTER,
+};
+
+static const AVFilterPad avfilter_vf_zscale_inputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad avfilter_vf_zscale_outputs[] = {
+    {
+        .name         = "default",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .config_props = config_props,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_zscale = {
+    .name            = "zscale",
+    .description     = NULL_IF_CONFIG_SMALL("Apply resizing, colorspace and bit depth conversion."),
+    .init_dict       = init_dict,
+    .query_formats   = query_formats,
+    .priv_size       = sizeof(ZScaleContext),
+    .priv_class      = &zscale_class,
+    .uninit          = uninit,
+    .inputs          = avfilter_vf_zscale_inputs,
+    .outputs         = avfilter_vf_zscale_outputs,
+    .process_command = process_command,
+};