From dd08b83c876275ae4741225a4820997c935b956d Mon Sep 17 00:00:00 2001 From: Stefano Sabatini Date: Sat, 16 Jan 2010 10:43:53 +0000 Subject: [PATCH] Implement null video source. Originally committed as revision 21240 to svn://svn.ffmpeg.org/ffmpeg/trunk --- doc/libavfilter.texi | 16 ++++++++ libavfilter/Makefile | 2 + libavfilter/allfilters.c | 2 + libavfilter/avfilter.h | 2 +- libavfilter/vsrc_nullsrc.c | 83 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 104 insertions(+), 1 deletion(-) create mode 100644 libavfilter/vsrc_nullsrc.c diff --git a/doc/libavfilter.texi b/doc/libavfilter.texi index 0e473fdfee..28f24bce9f 100644 --- a/doc/libavfilter.texi +++ b/doc/libavfilter.texi @@ -197,4 +197,20 @@ Flip the input video vertically. ./ffmpeg -i in.avi -vfilters "vflip" out.avi @end example +@chapter Available video sources + +Below is a description of the currently available video sources. + +@section nullsrc + +Null video source, never return images. It is mainly useful as a +template and to be employed in analysis / debugging tools. + +It accepts as optional parameter a string of the form +``width:height'', where ``width'' and ``height'' specify the size of +the configured source. + +The default values of ``width'' and ``height'' are respectively 352 +and 288 (corresponding to the CIF size format). + @bye diff --git a/libavfilter/Makefile b/libavfilter/Makefile index b8a8772bae..08d60800f4 100644 --- a/libavfilter/Makefile +++ b/libavfilter/Makefile @@ -20,4 +20,6 @@ OBJS-$(CONFIG_SCALE_FILTER) += vf_scale.o OBJS-$(CONFIG_SLICIFY_FILTER) += vf_slicify.o OBJS-$(CONFIG_VFLIP_FILTER) += vf_vflip.o +OBJS-$(CONFIG_NULLSRC_FILTER) += vsrc_nullsrc.o + include $(SUBDIR)../subdir.mak diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c index a4cbdade86..81eec21598 100644 --- a/libavfilter/allfilters.c +++ b/libavfilter/allfilters.c @@ -41,4 +41,6 @@ void avfilter_register_all(void) REGISTER_FILTER (SCALE, scale, vf); REGISTER_FILTER (SLICIFY, slicify, vf); REGISTER_FILTER (VFLIP, vflip, vf); + + REGISTER_FILTER (NULLSRC, nullsrc, vsrc); } diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h index 8f12d7d1d5..5b85427ac1 100644 --- a/libavfilter/avfilter.h +++ b/libavfilter/avfilter.h @@ -25,7 +25,7 @@ #include "libavutil/avutil.h" #define LIBAVFILTER_VERSION_MAJOR 1 -#define LIBAVFILTER_VERSION_MINOR 15 +#define LIBAVFILTER_VERSION_MINOR 16 #define LIBAVFILTER_VERSION_MICRO 0 #define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \ diff --git a/libavfilter/vsrc_nullsrc.c b/libavfilter/vsrc_nullsrc.c new file mode 100644 index 0000000000..ff14ea68b2 --- /dev/null +++ b/libavfilter/vsrc_nullsrc.c @@ -0,0 +1,83 @@ +/* + * 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 libavfilter/vsrc_nullsrc.c + * null video source + */ + +#include "avfilter.h" + +typedef struct { + int w, h; +} NullContext; + +static int init(AVFilterContext *ctx, const char *args, void *opaque) +{ + NullContext *priv = ctx->priv; + + priv->w = 352; + priv->h = 288; + + if (args) + sscanf(args, "%d:%d", &priv->w, &priv->h); + + if (priv->w <= 0 || priv->h <= 0) { + av_log(ctx, AV_LOG_ERROR, "Non-positive size values are not acceptable.\n"); + return -1; + } + + return 0; +} + +static int config_props(AVFilterLink *outlink) +{ + NullContext *priv = outlink->src->priv; + + outlink->w = priv->w; + outlink->h = priv->h; + + av_log(outlink->src, AV_LOG_INFO, "w:%d h:%d\n", priv->w, priv->h); + + return 0; +} + +static int request_frame(AVFilterLink *link) +{ + return -1; +} + +AVFilter avfilter_vsrc_nullsrc = { + .name = "nullsrc", + .description = "Null video source, never return images.", + + .init = init, + .priv_size = sizeof(NullContext), + + .inputs = (AVFilterPad[]) {{ .name = NULL}}, + + .outputs = (AVFilterPad[]) { + { + .name = "default", + .type = CODEC_TYPE_VIDEO, + .config_props = config_props, + .request_frame = request_frame, + }, + { .name = NULL} + }, +};