[FFmpeg-devel] [PATCH] avfilter: add mkmap source filter
Paul B Mahol
onemda at gmail.com
Sun Jan 29 01:37:33 EET 2017
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/filters.texi | 39 ++++++++++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/vsrc_mkmap.c | 163 +++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 204 insertions(+)
create mode 100644 libavfilter/vsrc_mkmap.c
diff --git a/doc/filters.texi b/doc/filters.texi
index cd1aaab..d1790ac 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -15248,6 +15248,45 @@ Set the initial y position. Must be a floating point value between
-100 and 100. Default value is -0.131825904205311970493132056385139.
@end table
+ at section mkmap
+
+Generate map of pixels for one of axis, either X or Y. Mainly useful
+as providing input frames for remap filter.
+
+This source accepts the following options:
+
+ at table @option
+
+ at item size, s
+Set the size of the output video. For the syntax of this option, check the
+ at ref{video size syntax,,"Video size" section in the ffmpeg-utils manual,ffmpeg-utils}.
+
+ at item rate, r
+Set the video rate, that is the number of frames generated per second.
+Default is 25.
+
+ at item expr, e
+Set map expression.
+
+The expressions can contain the following constants and functions:
+
+ at table @option
+ at item W
+ at item H
+The output width and height.
+
+ at item X
+ at item Y
+The current column and row.
+
+ at item N
+The current frame number, starting from 0.
+
+ at item T
+Time of the current frame, expressed in seconds.
+ at end table
+ at end table
+
@section mptestsrc
Generate various test patterns, as generated by the MPlayer test filter.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 91621d9..68e1923 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -321,6 +321,7 @@ OBJS-$(CONFIG_FREI0R_SRC_FILTER) += vf_frei0r.o
OBJS-$(CONFIG_HALDCLUTSRC_FILTER) += vsrc_testsrc.o
OBJS-$(CONFIG_LIFE_FILTER) += vsrc_life.o
OBJS-$(CONFIG_MANDELBROT_FILTER) += vsrc_mandelbrot.o
+OBJS-$(CONFIG_MKMAP_FILTER) += vsrc_mkmap.o
OBJS-$(CONFIG_MPTESTSRC_FILTER) += vsrc_mptestsrc.o
OBJS-$(CONFIG_NULLSRC_FILTER) += vsrc_testsrc.o
OBJS-$(CONFIG_RGBTESTSRC_FILTER) += vsrc_testsrc.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index d71d14a..1d8ca94 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -336,6 +336,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(HALDCLUTSRC, haldclutsrc, vsrc);
REGISTER_FILTER(LIFE, life, vsrc);
REGISTER_FILTER(MANDELBROT, mandelbrot, vsrc);
+ REGISTER_FILTER(MKMAP, mkmap, vsrc);
REGISTER_FILTER(MPTESTSRC, mptestsrc, vsrc);
REGISTER_FILTER(NULLSRC, nullsrc, vsrc);
REGISTER_FILTER(RGBTESTSRC, rgbtestsrc, vsrc);
diff --git a/libavfilter/vsrc_mkmap.c b/libavfilter/vsrc_mkmap.c
new file mode 100644
index 0000000..e699c5f
--- /dev/null
+++ b/libavfilter/vsrc_mkmap.c
@@ -0,0 +1,163 @@
+/*
+ * Copyright (c) 2017 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
+ */
+
+#include "libavutil/eval.h"
+#include "libavutil/opt.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "internal.h"
+#include "video.h"
+
+typedef struct MkMapContext {
+ const AVClass *class;
+
+ int w, h;
+ AVRational frame_rate;
+ char *expr_str;
+
+ AVExpr *expr;
+ int64_t pts;
+} MkMapContext;
+
+static const char *const var_names[] = {
+ "W", "H", "X", "Y", "N", "T",
+ NULL
+};
+
+enum var_name {
+ VAR_W, VAR_H, VAR_X, VAR_Y, VAR_N, VAR_T,
+ VAR_VARS_NB
+};
+
+#define OFFSET(x) offsetof(MkMapContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption mkmap_options[] = {
+ { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "hd720"}, 0, 0, FLAGS },
+ { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "hd720"}, 0, 0, FLAGS },
+ { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS },
+ { "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, INT_MAX, FLAGS },
+ { "expr", "set map expression", OFFSET(expr_str), AV_OPT_TYPE_STRING, {.str = "Y*W+X" }, 0, 0, FLAGS },
+ { "e", "set map expression", OFFSET(expr_str), AV_OPT_TYPE_STRING, {.str = "Y*W+X" }, 0, 0, FLAGS },
+ { NULL }
+};
+
+AVFILTER_DEFINE_CLASS(mkmap);
+
+static int query_formats(AVFilterContext *ctx)
+{
+ static const enum AVPixelFormat pix_fmts[] = {
+ AV_PIX_FMT_GRAY16,
+ AV_PIX_FMT_NONE
+ };
+
+ AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
+ if (!fmts_list)
+ return AVERROR(ENOMEM);
+ return ff_set_common_formats(ctx, fmts_list);
+}
+
+static int mkmap(MkMapContext *s, AVFrame *out, AVFilterLink *outlink)
+{
+ double var_values[VAR_VARS_NB];
+ uint16_t *dst;
+ int ret, x, y;
+
+ av_expr_free(s->expr);
+ s->expr = NULL;
+ ret = av_expr_parse(&s->expr, s->expr_str,
+ var_names, NULL, NULL, NULL, NULL, 0, s);
+ if (ret < 0) {
+ av_log(s, AV_LOG_ERROR,
+ "Error when parsing the expression '%s'.\n",
+ s->expr_str);
+ return AVERROR(EINVAL);
+ }
+
+ var_values[VAR_N] = outlink->frame_count_out,
+ var_values[VAR_T] = out->pts * av_q2d(outlink->time_base),
+ var_values[VAR_W] = out->width;
+ var_values[VAR_H] = out->height;
+
+ dst = (uint16_t *)out->data[0];
+ for (y = 0; y < out->height; y++) {
+ var_values[VAR_Y] = y;
+ for (x = 0; x < out->width; x++) {
+ var_values[VAR_X] = x;
+ dst[x] = av_expr_eval(s->expr, var_values, s);
+ }
+ dst += out->linesize[0] / 2;
+ }
+ out->pts++;
+
+ return ret;
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ MkMapContext *s = ctx->priv;
+
+ outlink->w = s->w;
+ outlink->h = s->h;
+ outlink->time_base = av_inv_q(s->frame_rate);
+
+ return 0;
+}
+
+static int request_frame(AVFilterLink *outlink)
+{
+ MkMapContext *s = outlink->src->priv;
+ AVFrame *out = ff_get_video_buffer(outlink, s->w, s->h);
+ if (!out)
+ return AVERROR(ENOMEM);
+ out->sample_aspect_ratio = (AVRational) {1, 1};
+ mkmap(s, out, outlink);
+ return ff_filter_frame(outlink, out);
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ MkMapContext *s = ctx->priv;
+
+ av_expr_free(s->expr);
+ s->expr = NULL;
+}
+
+static const AVFilterPad mkmap_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .request_frame = request_frame,
+ .config_props = config_props,
+ },
+ { NULL }
+};
+
+AVFilter ff_vsrc_mkmap = {
+ .name = "mkmap",
+ .description = NULL_IF_CONFIG_SMALL("Make mapping for pixels."),
+ .priv_size = sizeof(MkMapContext),
+ .priv_class = &mkmap_class,
+ .uninit = uninit,
+ .query_formats = query_formats,
+ .inputs = NULL,
+ .outputs = mkmap_outputs,
+};
--
2.9.3
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