avfilter: add remap filter

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

1 files changed, 337 insertions, 0 deletions

diff --git a/libavfilter/vf_remap.c b/libavfilter/vf_remap.c
new file mode 100644
index 0000000000..c6639fed42
--- /dev/null
+++ b/libavfilter/vf_remap.c
@@ -0,0 +1,337 @@
+/*
+ * Copyright (c) 2016 Floris Sluiter
+ *
+ * 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
+ * Pixel remap filter
+ * This filter copies pixel by pixel a source frame to a target frame.
+ * It remaps the pixels to a new x,y destination based on two files ymap/xmap.
+ * Map files are passed as a parameter and are in PGM format (P2 or P5),
+ * where the values are y(rows)/x(cols) coordinates of the source_frame.
+ * The *target* frame dimension is based on mapfile dimensions: specified in the
+ * header of the mapfile and reflected in the number of datavalues.
+ * Dimensions of ymap and xmap must be equal. Datavalues must be positive or zero.
+ * Any datavalue in the ymap or xmap which value is higher
+ * then the *source* frame height or width is silently ignored, leaving a
+ * blank/chromakey pixel. This can safely be used as a feature to create overlays.
+ *
+ * Algorithm digest:
+ * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
+ */
+
+#include "libavutil/imgutils.h"
+#include "libavutil/pixdesc.h"
+#include "libavutil/opt.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "framesync.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct RemapContext {
+    const AVClass *class;
+    int nb_planes;
+    int nb_components;
+    int step;
+    FFFrameSync fs;
+
+    void (*remap)(struct RemapContext *s, const AVFrame *in,
+                  const AVFrame *xin, const AVFrame *yin,
+                  AVFrame *out);
+} RemapContext;
+
+#define OFFSET(x) offsetof(RemapContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption remap_options[] = {
+    { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(remap);
+
+static int query_formats(AVFilterContext *ctx)
+{
+    static const enum AVPixelFormat pix_fmts[] = {
+        AV_PIX_FMT_YUVA444P,
+        AV_PIX_FMT_YUV444P,
+        AV_PIX_FMT_YUVJ444P,
+        AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
+        AV_PIX_FMT_ARGB, AV_PIX_FMT_ABGR, AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
+        AV_PIX_FMT_GBRP, AV_PIX_FMT_GBRAP,
+        AV_PIX_FMT_NONE
+    };
+    static const enum AVPixelFormat map_fmts[] = {
+        AV_PIX_FMT_GRAY16,
+        AV_PIX_FMT_NONE
+    };
+    AVFilterFormats *pix_formats = NULL, *map_formats = NULL;
+    int ret;
+
+    if (!(pix_formats = ff_make_format_list(pix_fmts)) ||
+        !(map_formats = ff_make_format_list(map_fmts))) {
+        ret = AVERROR(ENOMEM);
+        goto fail;
+    }
+    if ((ret = ff_formats_ref(pix_formats, &ctx->inputs[0]->out_formats)) < 0 ||
+        (ret = ff_formats_ref(map_formats, &ctx->inputs[1]->out_formats)) < 0 ||
+        (ret = ff_formats_ref(map_formats, &ctx->inputs[2]->out_formats)) < 0 ||
+        (ret = ff_formats_ref(pix_formats, &ctx->outputs[0]->in_formats)) < 0)
+        goto fail;
+    return 0;
+fail:
+    if (pix_formats)
+        av_freep(&pix_formats->formats);
+    av_freep(&pix_formats);
+    if (map_formats)
+        av_freep(&map_formats->formats);
+    av_freep(&map_formats);
+    return ret;
+}
+
+/**
+ * remap_planar algorithm expects planes of same size
+ * pixels are copied from source to target using :
+ * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
+ */
+static void remap_planar(RemapContext *s, const AVFrame *in,
+                         const AVFrame *xin, const AVFrame *yin,
+                         AVFrame *out)
+{
+    const int xlinesize = xin->linesize[0] / 2;
+    const int ylinesize = yin->linesize[0] / 2;
+    int x , y, plane;
+
+    for (plane = 0; plane < s->nb_planes ; plane++) {
+        uint8_t *dst         = out->data[plane];
+        const int dlinesize  = out->linesize[plane];
+        const uint8_t *src   = in->data[plane];
+        const int slinesize  = in->linesize[plane];
+        const uint16_t *xmap = (const uint16_t *)xin->data[0];
+        const uint16_t *ymap = (const uint16_t *)yin->data[0];
+
+        for (y = 0; y < out->height; y++) {
+            for (x = 0; x < out->width; x++) {
+                if (ymap[x] < in->height && xmap[x] < in->width) {
+                    dst[x] = src[ymap[x] * slinesize + xmap[x]];
+                } else {
+                    dst[x] = 0;
+                }
+            }
+            dst  += dlinesize;
+            xmap += xlinesize;
+            ymap += ylinesize;
+        }
+    }
+}
+
+/**
+ * remap_packed algorithm expects pixels with both padded bits (step) and
+ * number of components correctly set.
+ * pixels are copied from source to target using :
+ * Target_frame[y][x] = Source_frame[ ymap[y][x] ][ [xmap[y][x] ];
+ */
+static void remap_packed(RemapContext *s, const AVFrame *in,
+                         const AVFrame *xin, const AVFrame *yin,
+                         AVFrame *out)
+{
+    uint8_t *dst = out->data[0];
+    const uint8_t *src  = in->data[0];
+    const int dlinesize = out->linesize[0];
+    const int slinesize = in->linesize[0];
+    const int xlinesize = xin->linesize[0] / 2;
+    const int ylinesize = yin->linesize[0] / 2;
+    const uint16_t *xmap = (const uint16_t *)xin->data[0];
+    const uint16_t *ymap = (const uint16_t *)yin->data[0];
+    const int step = s->step;
+    int c, x, y;
+
+    for (y = 0; y < out->height; y++) {
+        for (x = 0; x < out->width; x++) {
+            for (c = 0; c < s->nb_components; c++) {
+                if (ymap[x] < in->height && xmap[x] < in->width) {
+                    dst[x * step + c] = src[ymap[x] * slinesize + xmap[x] * step + c];
+                } else {
+                    dst[x * step + c] = 0;
+                }
+            }
+        }
+        dst  += dlinesize;
+        xmap += xlinesize;
+        ymap += ylinesize;
+    }
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+    AVFilterContext *ctx = inlink->dst;
+    RemapContext *s = ctx->priv;
+    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
+
+    s->nb_planes = av_pix_fmt_count_planes(inlink->format);
+    s->nb_components = desc->nb_components;
+
+    if (s->nb_planes > 1 || s->nb_components == 1) {
+        s->remap = remap_planar;
+    } else {
+        s->remap = remap_packed;
+    }
+
+    s->step = av_get_padded_bits_per_pixel(desc) >> 3;
+    return 0;
+}
+
+static int process_frame(FFFrameSync *fs)
+{
+    AVFilterContext *ctx = fs->parent;
+    RemapContext *s = fs->opaque;
+    AVFilterLink *outlink = ctx->outputs[0];
+    AVFrame *out, *in, *xpic, *ypic;
+    int ret;
+
+    if ((ret = ff_framesync_get_frame(&s->fs, 0, &in,   0)) < 0 ||
+        (ret = ff_framesync_get_frame(&s->fs, 1, &xpic, 0)) < 0 ||
+        (ret = ff_framesync_get_frame(&s->fs, 2, &ypic, 0)) < 0)
+        return ret;
+
+    if (ctx->is_disabled) {
+        out = av_frame_clone(in);
+        if (!out)
+            return AVERROR(ENOMEM);
+    } else {
+        out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+        if (!out)
+            return AVERROR(ENOMEM);
+        av_frame_copy_props(out, in);
+
+        s->remap(s, in, xpic, ypic, out);
+    }
+    out->pts = av_rescale_q(in->pts, s->fs.time_base, outlink->time_base);
+
+    return ff_filter_frame(outlink, out);
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+    AVFilterContext *ctx = outlink->src;
+    RemapContext *s = ctx->priv;
+    AVFilterLink *srclink = ctx->inputs[0];
+    AVFilterLink *xlink = ctx->inputs[1];
+    AVFilterLink *ylink = ctx->inputs[2];
+    FFFrameSyncIn *in;
+    int ret;
+
+    if (xlink->w != ylink->w || xlink->h != ylink->h) {
+        av_log(ctx, AV_LOG_ERROR, "Second input link %s parameters "
+               "(size %dx%d) do not match the corresponding "
+               "third input link %s parameters (%dx%d)\n",
+               ctx->input_pads[1].name, xlink->w, xlink->h,
+               ctx->input_pads[2].name, ylink->w, ylink->h);
+        return AVERROR(EINVAL);
+    }
+
+    outlink->w = xlink->w;
+    outlink->h = xlink->h;
+    outlink->time_base = srclink->time_base;
+    outlink->sample_aspect_ratio = srclink->sample_aspect_ratio;
+    outlink->frame_rate = srclink->frame_rate;
+
+    ret = ff_framesync_init(&s->fs, ctx, 3);
+    if (ret < 0)
+        return ret;
+
+    in = s->fs.in;
+    in[0].time_base = srclink->time_base;
+    in[1].time_base = xlink->time_base;
+    in[2].time_base = ylink->time_base;
+    in[0].sync   = 2;
+    in[0].before = EXT_STOP;
+    in[0].after  = EXT_STOP;
+    in[1].sync   = 1;
+    in[1].before = EXT_NULL;
+    in[1].after  = EXT_INFINITY;
+    in[2].sync   = 1;
+    in[2].before = EXT_NULL;
+    in[2].after  = EXT_INFINITY;
+    s->fs.opaque   = s;
+    s->fs.on_event = process_frame;
+
+    return ff_framesync_configure(&s->fs);
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
+{
+    RemapContext *s = inlink->dst->priv;
+    return ff_framesync_filter_frame(&s->fs, inlink, buf);
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+    RemapContext *s = outlink->src->priv;
+    return ff_framesync_request_frame(&s->fs, outlink);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+    RemapContext *s = ctx->priv;
+
+    ff_framesync_uninit(&s->fs);
+}
+
+static const AVFilterPad remap_inputs[] = {
+    {
+        .name         = "source",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+        .config_props = config_input,
+    },
+    {
+        .name         = "xmap",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+    },
+    {
+        .name         = "ymap",
+        .type         = AVMEDIA_TYPE_VIDEO,
+        .filter_frame = filter_frame,
+    },
+    { NULL }
+};
+
+static const AVFilterPad remap_outputs[] = {
+    {
+        .name          = "default",
+        .type          = AVMEDIA_TYPE_VIDEO,
+        .config_props  = config_output,
+        .request_frame = request_frame,
+    },
+    { NULL }
+};
+
+AVFilter ff_vf_remap = {
+    .name          = "remap",
+    .description   = NULL_IF_CONFIG_SMALL("Remap pixels"),
+    .priv_size     = sizeof(RemapContext),
+    .uninit        = uninit,
+    .query_formats = query_formats,
+    .inputs        = remap_inputs,
+    .outputs       = remap_outputs,
+    .priv_class    = &remap_class,
+    .flags         = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
+};