lavfi: port phase filter from libmpcodecs

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

1 files changed, 320 insertions, 0 deletions

diff --git a/libavfilter/vf_phase.c b/libavfilter/vf_phase.c
new file mode 100644
index 0000000000..04e59cb4f2
--- /dev/null
+++ b/libavfilter/vf_phase.c
@@ -0,0 +1,320 @@
+/*
+ * Copyright (c) 2004 Ville Saari
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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 "libavutil/avassert.h"
+#include "libavutil/imgutils.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/opt.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+
+enum PhaseMode {
+    PROGRESSIVE,
+    TOP_FIRST,
+    BOTTOM_FIRST,
+    TOP_FIRST_ANALYZE,
+    BOTTOM_FIRST_ANALYZE,
+    ANALYZE,
+    FULL_ANALYZE,
+    AUTO,
+    AUTO_ANALYZE
+};
+
+typedef struct PhaseContext {
+    const AVClass *class;
+    enum PhaseMode mode;
+    AVFrame *frame;
+    int nb_planes;
+    int planeheight[4];
+    int linesize[4];
+} PhaseContext;
+
+#define OFFSET(x) offsetof(PhaseContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+#define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, 0, 0, FLAGS, unit }
+
+static const AVOption phase_options[] = {
+    { "mode", "set phase mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=AUTO_ANALYZE}, PROGRESSIVE, AUTO_ANALYZE, FLAGS, "mode" },
+    CONST("p", "progressive",          PROGRESSIVE,          "mode"),
+    CONST("t", "top first",            TOP_FIRST,            "mode"),
+    CONST("b", "bottom first",         BOTTOM_FIRST,         "mode"),
+    CONST("T", "top first analyze",    TOP_FIRST_ANALYZE,    "mode"),
+    CONST("B", "bottom first analyze", BOTTOM_FIRST_ANALYZE, "mode"),
+    CONST("u", "analyze",              ANALYZE,              "mode"),
+    CONST("U", "full analyze",         FULL_ANALYZE,         "mode"),
+    CONST("a", "auto",                 AUTO,                 "mode"),
+    CONST("A", "auto analyze",         AUTO_ANALYZE,         "mode"),
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(phase);
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUVA444P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA420P,
+        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_YUVJ422P,AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ411P,
+        AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE
+    };
+
+    ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
+    return 0;
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+    PhaseContext *s = inlink->dst->priv;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+    int ret;
+
+    if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
+        return ret;
+
+    s->planeheight[1] = s->planeheight[2] = FF_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
+    s->planeheight[0] = s->planeheight[3] = inlink->h;
+
+    s->nb_planes = av_pix_fmt_count_planes(inlink->format);
+
+    return 0;
+}
+
+/*
+ * This macro interpolates the value of both fields at a point halfway
+ * between lines and takes the squared difference. In field resolution
+ * the point is a quarter pixel below a line in one field and a quarter
+ * pixel above a line in other.
+ *
+ * (The result is actually multiplied by 25)
+ */
+#define DIFF(a, as, b, bs) (t = ((*a - b[bs]) << 2) + a[as << 1] - b[-bs], t * t)
+
+/*
+ * Find which field combination has the smallest average squared difference
+ * between the fields.
+ */
+static enum PhaseMode analyze_plane(AVFilterContext *ctx, PhaseContext *s,
+                                    AVFrame *old, AVFrame *new)
+{
+    double bdiff, tdiff, pdiff, scale;
+    const int ns = new->linesize[0];
+    const int os = old->linesize[0];
+    uint8_t *nptr = new->data[0];
+    uint8_t *optr = old->data[0];
+    const int h = new->height;
+    const int w = new->width;
+    int bdif, tdif, pdif;
+    enum PhaseMode mode = s->mode;
+    uint8_t *end, *rend;
+    int top, t;
+
+    if (mode == AUTO) {
+        mode = new->interlaced_frame ? new->top_field_first ?
+               TOP_FIRST : BOTTOM_FIRST : PROGRESSIVE;
+    } else if (mode == AUTO_ANALYZE) {
+        mode = new->interlaced_frame ? new->top_field_first ?
+               TOP_FIRST_ANALYZE : BOTTOM_FIRST_ANALYZE : FULL_ANALYZE;
+    }
+
+    if (mode <= BOTTOM_FIRST) {
+        bdiff = pdiff = tdiff = 65536.0;
+    } else {
+        bdiff = pdiff = tdiff = 0.0;
+
+        for (end = nptr + (h - 2) * ns, nptr += ns, optr += os, top = 0;
+             nptr < end; nptr += ns - w, optr += os - w, top ^= 1) {
+            pdif = tdif = bdif = 0;
+
+            switch (mode) {
+            case TOP_FIRST_ANALYZE:
+                if (top) {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        tdif += DIFF(nptr, ns, optr, os);
+                    }
+                } else {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        tdif += DIFF(optr, os, nptr, ns);
+                    }
+                }
+                break;
+            case BOTTOM_FIRST_ANALYZE:
+                if (top) {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        bdif += DIFF(optr, os, nptr, ns);
+                    }
+                } else {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        bdif += DIFF(nptr, ns, optr, os);
+                    }
+                }
+                break;
+            case ANALYZE:
+                if (top) {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        tdif += DIFF(nptr, ns, optr, os);
+                        bdif += DIFF(optr, os, nptr, ns);
+                    }
+                } else {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        bdif += DIFF(nptr, ns, optr, os);
+                        tdif += DIFF(optr, os, nptr, ns);
+                    }
+                }
+                break;
+            case FULL_ANALYZE:
+                if (top) {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        tdif += DIFF(nptr, ns, optr, os);
+                        bdif += DIFF(optr, os, nptr, ns);
+                    }
+                } else {
+                    for (rend = nptr + w; nptr < rend; nptr++, optr++) {
+                        pdif += DIFF(nptr, ns, nptr, ns);
+                        bdif += DIFF(nptr, ns, optr, os);
+                        tdif += DIFF(optr, os, nptr, ns);
+                    }
+                }
+                break;
+            default:
+                av_assert0(0);
+            }
+
+            pdiff += (double)pdif;
+            tdiff += (double)tdif;
+            bdiff += (double)bdif;
+        }
+
+        scale = 1.0 / (w * (h - 3)) / 25.0;
+        pdiff *= scale;
+        tdiff *= scale;
+        bdiff *= scale;
+
+        if (mode == TOP_FIRST_ANALYZE) {
+            bdiff = 65536.0;
+        } else if (mode == BOTTOM_FIRST_ANALYZE) {
+            tdiff = 65536.0;
+        } else if (mode == ANALYZE) {
+            pdiff = 65536.0;
+        }
+
+        if (bdiff < pdiff && bdiff < tdiff) {
+            mode = BOTTOM_FIRST;
+        } else if (tdiff < pdiff && tdiff < bdiff) {
+            mode = TOP_FIRST;
+        } else {
+            mode = PROGRESSIVE;
+        }
+    }
+
+    av_log(ctx, AV_LOG_DEBUG, "mode=%c tdiff=%f bdiff=%f pdiff=%f\n",
+           mode == BOTTOM_FIRST ? 'b' : mode == TOP_FIRST ? 't' : 'p',
+           tdiff, bdiff, pdiff);
+    return mode;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *in)
+{
+    AVFilterContext *ctx = inlink->dst;
+    AVFilterLink *outlink = ctx->outputs[0];
+    PhaseContext *s = ctx->priv;
+    enum PhaseMode mode = s->mode;
+    int plane, top, y;
+    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);
+
+    if (!s->frame) {
+        mode = PROGRESSIVE;
+        s->frame = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+        if (!s->frame) {
+            av_frame_free(&in);
+            av_frame_free(&out);
+            return AVERROR(ENOMEM);
+        }
+    } else {
+        mode = analyze_plane(ctx, s, s->frame, in);
+    }
+
+    for (plane = 0; plane < s->nb_planes; plane++) {
+        uint8_t *buf = s->frame->data[plane];
+        uint8_t *from = in->data[plane];
+        uint8_t *to = out->data[plane];
+
+        for (y = 0, top = 1; y < s->planeheight[plane]; y++, top ^= 1) {
+            memcpy(to, mode == (top ? BOTTOM_FIRST : TOP_FIRST) ? buf : from, s->linesize[plane]);
+            memcpy(buf, from, s->linesize[plane]);
+
+            buf += s->frame->linesize[plane];
+            from += in->linesize[plane];
+            to += out->linesize[plane];
+        }
+    }
+
+    av_frame_free(&in);
+    return ff_filter_frame(outlink, out);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    PhaseContext *s = ctx->priv;
+
+    av_frame_free(&s->frame);
+}
+
+static const AVFilterPad phase_inputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .filter_frame  = filter_frame,
+        .config_props  = config_input,
+    },
+    { NULL }
+};
+
+static const AVFilterPad phase_outputs[] = {
+    {
+        .name = "default",
+        .type = AVMEDIA_TYPE_VIDEO,
+    },
+    { NULL }
+};
+
+AVFilter avfilter_vf_phase = {
+    .name          = "phase",
+    .description   = NULL_IF_CONFIG_SMALL("Phase shift fields."),
+    .priv_size     = sizeof(PhaseContext),
+    .priv_class    = &phase_class,
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = phase_inputs,
+    .outputs       = phase_outputs,
+};