[FFmpeg-devel] [PATCH] lavfi: avectorscope filter
Paul B Mahol
onemda at gmail.com
Mon Apr 29 15:17:58 CEST 2013
Signed-off-by: Paul B Mahol <onemda at gmail.com>
---
doc/filters.texi | 44 +++++++
libavfilter/Makefile | 1 +
libavfilter/allfilters.c | 1 +
libavfilter/avf_avectorscope.c | 262 +++++++++++++++++++++++++++++++++++++++++
4 files changed, 308 insertions(+)
create mode 100644 libavfilter/avf_avectorscope.c
diff --git a/doc/filters.texi b/doc/filters.texi
index a1d5581..8f030a3 100644
--- a/doc/filters.texi
+++ b/doc/filters.texi
@@ -7142,6 +7142,50 @@ tools.
Below is a description of the currently available multimedia filters.
+ at section avectorscope
+
+Convert input audio to a video output, representing the audio vector
+scope.
+
+The filter is used to measure the difference between channels of stereo
+audio stream. A monoaural signal, consisting of identical left and right
+signal, results in straight vertical line. Any stereo separation is visible
+as a deviation from this line, creating a Lissajous figure.
+If the straight (or deviation from it) but horizontal line appears this
+indicates that the left and right channels are out of phase.
+
+The filter accepts the following options:
+
+ at table @option
+ at item mode, m
+Set the vectorscope mode. Default value is @code{lissajous}.
+
+Available values are:
+ at table @samp
+ at item lissajous
+Lissajous rotated by 45 degrees.
+
+ at item lissajous_xy
+Same as above but not rotated.
+ at end table
+
+ at item size, s
+Set the video size for the output. Default value is @code{320x240}.
+
+ at item rate, r
+Set the output frame rate. Default value is @code{25}.
+
+ at item rc
+ at item gc
+ at item bc
+Specify the red, green and blue contrast.
+
+ at item rf
+ at item gf
+ at item bf
+Specify the red, green and blue fade.
+ at end table
+
@section concat
Concatenate audio and video streams, joining them together one after the
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 6f41d71..9f1f96b 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -220,6 +220,7 @@ OBJS-$(CONFIG_MP_FILTER) += libmpcodecs/vf_uspp.o
OBJS-$(CONFIG_MP_FILTER) += libmpcodecs/pullup.o
# multimedia filters
+OBJS-$(CONFIG_AVECTORSCOPE_FILTER) += avf_avectorscope.o
OBJS-$(CONFIG_CONCAT_FILTER) += avf_concat.o
OBJS-$(CONFIG_SHOWSPECTRUM_FILTER) += avf_showspectrum.o
OBJS-$(CONFIG_SHOWWAVES_FILTER) += avf_showwaves.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 97e558b..53e54aa 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -196,6 +196,7 @@ void avfilter_register_all(void)
REGISTER_FILTER(NULLSINK, nullsink, vsink);
/* multimedia filters */
+ REGISTER_FILTER(AVECTORSCOPE, avectorscope, avf);
REGISTER_FILTER(CONCAT, concat, avf);
REGISTER_FILTER(SHOWSPECTRUM, showspectrum, avf);
REGISTER_FILTER(SHOWWAVES, showwaves, avf);
diff --git a/libavfilter/avf_avectorscope.c b/libavfilter/avf_avectorscope.c
new file mode 100644
index 0000000..a99a09c
--- /dev/null
+++ b/libavfilter/avf_avectorscope.c
@@ -0,0 +1,262 @@
+/*
+ * Copyright (c) 2013 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
+ * audio to video multimedia vector scope filter
+ */
+
+#include "libavutil/avassert.h"
+#include "libavutil/channel_layout.h"
+#include "libavutil/opt.h"
+#include "libavutil/parseutils.h"
+#include "avfilter.h"
+#include "formats.h"
+#include "audio.h"
+#include "video.h"
+#include "internal.h"
+
+enum VectorScopeMode {
+ LISSAJOUS,
+ LISSAJOUS_XY,
+ MODE_NB,
+};
+
+typedef struct AudioVectorScopeContext {
+ const AVClass *class;
+ AVFrame *outpicref;
+ int w, h;
+ int hw, hh;
+ enum VectorScopeMode mode;
+ int contrast[3];
+ int fade[3];
+ AVRational frame_rate;
+} AudioVectorScopeContext;
+
+#define OFFSET(x) offsetof(AudioVectorScopeContext, x)
+#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
+
+static const AVOption avectorscope_options[] = {
+ { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=LISSAJOUS}, 0, MODE_NB-1, FLAGS, "mode" },
+ { "m", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=LISSAJOUS}, 0, MODE_NB-1, FLAGS, "mode" },
+ { "lissajous", "", 0, AV_OPT_TYPE_CONST, {.i64=LISSAJOUS}, 0, 0, FLAGS, "mode" },
+ { "lissajous_xy", "", 0, AV_OPT_TYPE_CONST, {.i64=LISSAJOUS_XY}, 0, 0, FLAGS, "mode" },
+ { "rate", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, 0, FLAGS },
+ { "r", "set video rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, 0, FLAGS },
+ { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="320x240"}, 0, 0, FLAGS },
+ { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="320x240"}, 0, 0, FLAGS },
+ { "rc", "set red contrast", OFFSET(contrast[0]), AV_OPT_TYPE_INT, {.i64=40}, 1, 255, FLAGS },
+ { "gc", "set green contrast", OFFSET(contrast[1]), AV_OPT_TYPE_INT, {.i64=160}, 1, 255, FLAGS },
+ { "bc", "set blue contrast", OFFSET(contrast[2]), AV_OPT_TYPE_INT, {.i64=80}, 1, 255, FLAGS },
+ { "rf", "set red fade", OFFSET(fade[0]), AV_OPT_TYPE_INT, {.i64=15}, 0, 255, FLAGS },
+ { "gf", "set green fade", OFFSET(fade[1]), AV_OPT_TYPE_INT, {.i64=10}, 0, 255, FLAGS },
+ { "bf", "set blue fade", OFFSET(fade[2]), AV_OPT_TYPE_INT, {.i64=5}, 0, 255, FLAGS },
+ {NULL},
+};
+
+AVFILTER_DEFINE_CLASS(avectorscope);
+
+static void draw_dot(AudioVectorScopeContext *p, unsigned x, unsigned y)
+{
+ const int linesize = p->outpicref->linesize[0];
+ uint8_t *dst;
+
+ y = FFMIN(y, p->h - 1);
+ x = FFMIN(x, p->w - 1);
+
+ dst = &p->outpicref->data[0][y * linesize + x * 4];
+ dst[0] = FFMIN(dst[0] + p->contrast[0], 255);
+ dst[1] = FFMIN(dst[1] + p->contrast[1], 255);
+ dst[2] = FFMIN(dst[2] + p->contrast[2], 255);
+}
+
+static void fade(AudioVectorScopeContext *p)
+{
+ const int linesize = p->outpicref->linesize[0];
+ int i, j;
+
+ if (p->fade[0] || p->fade[1] || p->fade[2]) {
+ uint8_t *d = p->outpicref->data[0];
+ for (i = 0; i < p->h; i++) {
+ for (j = 0; j < p->w*4; j+=4) {
+ d[j+0] = FFMAX(d[j+0] - p->fade[0], 0);
+ d[j+1] = FFMAX(d[j+1] - p->fade[1], 0);
+ d[j+2] = FFMAX(d[j+2] - p->fade[2], 0);
+ }
+ d += linesize;
+ }
+ }
+
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ AudioVectorScopeContext *p = ctx->priv;
+
+ av_frame_free(&p->outpicref);
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ AVFilterFormats *formats = NULL;
+ AVFilterChannelLayouts *layout = NULL;
+ AVFilterLink *inlink = ctx->inputs[0];
+ AVFilterLink *outlink = ctx->outputs[0];
+ static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_NONE };
+ static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGBA, AV_PIX_FMT_NONE };
+
+ formats = ff_make_format_list(sample_fmts);
+ if (!formats)
+ return AVERROR(ENOMEM);
+ ff_formats_ref(formats, &inlink->out_formats);
+
+ ff_add_channel_layout(&layout, AV_CH_LAYOUT_STEREO);
+ ff_channel_layouts_ref(layout, &inlink->out_channel_layouts);
+
+ formats = ff_all_samplerates();
+ if (!formats)
+ return AVERROR(ENOMEM);
+ ff_formats_ref(formats, &inlink->out_samplerates);
+
+ formats = ff_make_format_list(pix_fmts);
+ if (!formats)
+ return AVERROR(ENOMEM);
+ ff_formats_ref(formats, &outlink->in_formats);
+
+ return 0;
+}
+
+static int config_input(AVFilterLink *inlink)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AudioVectorScopeContext *p = ctx->priv;
+ int nb_samples;
+
+ nb_samples = FFMAX(1024, ((double)inlink->sample_rate / av_q2d(p->frame_rate)) + 0.5);
+ inlink->partial_buf_size =
+ inlink->min_samples =
+ inlink->max_samples = nb_samples;
+
+ return 0;
+}
+
+static int config_output(AVFilterLink *outlink)
+{
+ AudioVectorScopeContext *p = outlink->src->priv;
+ int size;
+
+ outlink->w = p->w;
+ outlink->h = p->h;
+ outlink->sample_aspect_ratio = (AVRational){1,1};
+ outlink->frame_rate = p->frame_rate;
+ p->outpicref = ff_get_video_buffer(outlink, outlink->w, outlink->h);
+ if (!p->outpicref)
+ return AVERROR(ENOMEM);
+ size = outlink->h * p->outpicref->linesize[0];
+ memset(p->outpicref->data[0] + size, 0, FFABS(size));
+
+ p->hw = p->w / 2;
+ p->hh = p->h / 2;
+
+ return 0;
+}
+
+static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
+{
+ AVFilterContext *ctx = inlink->dst;
+ AVFilterLink *outlink = ctx->outputs[0];
+ AudioVectorScopeContext *p = ctx->priv;
+
+ p->outpicref->pts = insamples->pts;
+
+ const int hw = p->hw;
+ const int hh = p->hh;
+ unsigned x, y;
+ int i;
+
+ fade(p);
+
+ switch (insamples->format) {
+ case AV_SAMPLE_FMT_S16:
+ for (i = 0; i < insamples->nb_samples; i++) {
+ int16_t *src = (int16_t *)insamples->data[0] + i * 2;
+
+ if (p->mode == LISSAJOUS) {
+ x = ((src[1] - src[0]) / (float)(UINT16_MAX) + 1) * hw;
+ y = (1.0 - (src[0] + src[1]) / (float)UINT16_MAX) * hh;
+ } else {
+ x = (src[1] / (float)INT16_MAX + 1) * hw;
+ y = (src[0] / (float)INT16_MAX + 1) * hh;
+ }
+
+ draw_dot(p, x, y);
+ }
+ break;
+ case AV_SAMPLE_FMT_FLT:
+ for (i = 0; i < insamples->nb_samples; i++) {
+ float *src = (float *)insamples->data[0] + i * 2;
+
+ if (p->mode == LISSAJOUS) {
+ x = ((src[1] - src[0]) / 2 + 1) * hw;
+ y = (1.0 - (src[0] + src[1]) / 2) * hh;
+ } else {
+ x = (src[1] + 1) * hw;
+ y = (src[0] + 1) * hh;
+ }
+
+ draw_dot(p, x, y);
+ }
+ break;
+ }
+
+ av_frame_free(&insamples);
+
+ return ff_filter_frame(outlink, av_frame_clone(p->outpicref));
+}
+
+static const AVFilterPad audiovectorscope_inputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_AUDIO,
+ .config_props = config_input,
+ .filter_frame = filter_frame,
+ },
+ { NULL }
+};
+
+static const AVFilterPad audiovectorscope_outputs[] = {
+ {
+ .name = "default",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .config_props = config_output,
+ },
+ { NULL }
+};
+
+AVFilter avfilter_avf_avectorscope = {
+ .name = "avectorscope",
+ .description = NULL_IF_CONFIG_SMALL("Display audio vector scope."),
+ .uninit = uninit,
+ .query_formats = query_formats,
+ .priv_size = sizeof(AudioVectorScopeContext),
+ .inputs = audiovectorscope_inputs,
+ .outputs = audiovectorscope_outputs,
+ .priv_class = &avectorscope_class,
+};
--
1.7.11.2
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