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-rw-r--r--doc/libavfilter.texi25
-rw-r--r--libavfilter/Makefile1
-rw-r--r--libavfilter/allfilters.c1
-rw-r--r--libavfilter/avfilter.h2
-rw-r--r--libavfilter/vf_scale.c203
5 files changed, 231 insertions, 1 deletions
diff --git a/doc/libavfilter.texi b/doc/libavfilter.texi
index 3073b8a1f7..17f731ba87 100644
--- a/doc/libavfilter.texi
+++ b/doc/libavfilter.texi
@@ -164,6 +164,31 @@ not specified it will use the default value of 16.
Adding this in the beginning of filter chains should make filtering
faster due to better use of the memory cache.
+@section scale
+
+Scale the input video to width:height and/or convert the image format.
+
+For example the command:
+
+@example
+./ffmpeg -i in.avi -vfilters "scale=200:100" out.avi
+@end example
+
+will scale the input video to a size of 200x100.
+
+If the input image format is different from the format requested by
+the next filter, the scale filter will convert the input to the
+requested format.
+
+If the value for ``width'' or ``height'' is 0, the respective input
+size is used for the output.
+
+If the value for ``width'' or ``height'' is -1, the scale filter will
+use, for the respective output size, a value that maintains the aspect
+ratio of the input image.
+
+The default value of ``width'' and ``height'' is 0.
+
@section vflip
Flip the input video vertically.
diff --git a/libavfilter/Makefile b/libavfilter/Makefile
index 295bd58f32..b8a8772bae 100644
--- a/libavfilter/Makefile
+++ b/libavfilter/Makefile
@@ -16,6 +16,7 @@ OBJS-$(CONFIG_CROP_FILTER) += vf_crop.o
OBJS-$(CONFIG_FORMAT_FILTER) += vf_format.o
OBJS-$(CONFIG_NOFORMAT_FILTER) += vf_format.o
OBJS-$(CONFIG_NULL_FILTER) += vf_null.o
+OBJS-$(CONFIG_SCALE_FILTER) += vf_scale.o
OBJS-$(CONFIG_SLICIFY_FILTER) += vf_slicify.o
OBJS-$(CONFIG_VFLIP_FILTER) += vf_vflip.o
diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c
index 6ee13df238..a4cbdade86 100644
--- a/libavfilter/allfilters.c
+++ b/libavfilter/allfilters.c
@@ -38,6 +38,7 @@ void avfilter_register_all(void)
REGISTER_FILTER (FORMAT, format, vf);
REGISTER_FILTER (NOFORMAT, noformat, vf);
REGISTER_FILTER (NULL, null, vf);
+ REGISTER_FILTER (SCALE, scale, vf);
REGISTER_FILTER (SLICIFY, slicify, vf);
REGISTER_FILTER (VFLIP, vflip, vf);
}
diff --git a/libavfilter/avfilter.h b/libavfilter/avfilter.h
index 9048aa4daa..a2a57729a7 100644
--- a/libavfilter/avfilter.h
+++ b/libavfilter/avfilter.h
@@ -23,7 +23,7 @@
#define AVFILTER_AVFILTER_H
#define LIBAVFILTER_VERSION_MAJOR 1
-#define LIBAVFILTER_VERSION_MINOR 7
+#define LIBAVFILTER_VERSION_MINOR 8
#define LIBAVFILTER_VERSION_MICRO 0
#define LIBAVFILTER_VERSION_INT AV_VERSION_INT(LIBAVFILTER_VERSION_MAJOR, \
diff --git a/libavfilter/vf_scale.c b/libavfilter/vf_scale.c
new file mode 100644
index 0000000000..27fcdcb2cb
--- /dev/null
+++ b/libavfilter/vf_scale.c
@@ -0,0 +1,203 @@
+/*
+ * copyright (c) 2007 Bobby Bingham
+ *
+ * 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/vf_scale.c
+ * scale video filter
+ */
+
+#include "avfilter.h"
+#include "libswscale/swscale.h"
+
+typedef struct {
+ struct SwsContext *sws; ///< software scaler context
+
+ /**
+ * New dimensions. Special values are:
+ * 0 = original width/height
+ * -1 = keep original aspect
+ */
+ int w, h;
+
+ int hsub, vsub; ///< chroma subsampling
+ int slice_y; ///< top of current output slice
+ int slice_dir; ///< detected slice direction order for the current frame
+ int input_is_pal; ///< set to 1 if the input format is paletted
+} ScaleContext;
+
+static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
+{
+ ScaleContext *scale = ctx->priv;
+
+ if (args)
+ sscanf(args, "%d:%d", &scale->w, &scale->h);
+
+ /* sanity check params */
+ if (scale->w < -1 || scale->h < -1) {
+ av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
+ return -1;
+ }
+ if (scale->w == -1 && scale->h == -1)
+ scale->w = scale->h = 0;
+
+ return 0;
+}
+
+static av_cold void uninit(AVFilterContext *ctx)
+{
+ ScaleContext *scale = ctx->priv;
+ sws_freeContext(scale->sws);
+ scale->sws = NULL;
+}
+
+static int query_formats(AVFilterContext *ctx)
+{
+ AVFilterFormats *formats;
+
+ if (ctx->inputs[0]) {
+ formats = avfilter_all_colorspaces();
+ avfilter_formats_ref(formats, &ctx->inputs[0]->out_formats);
+ }
+ if (ctx->outputs[0]) {
+ formats = avfilter_all_colorspaces();
+ avfilter_formats_ref(formats, &ctx->outputs[0]->in_formats);
+ }
+
+ return 0;
+}
+
+static int config_props(AVFilterLink *outlink)
+{
+ AVFilterContext *ctx = outlink->src;
+ AVFilterLink *inlink = outlink->src->inputs[0];
+ ScaleContext *scale = ctx->priv;
+ int64_t w, h;
+
+ if (!(w = scale->w))
+ w = inlink->w;
+ if (!(h = scale->h))
+ h = inlink->h;
+ if (w == -1)
+ w = av_rescale(h, inlink->w, inlink->h);
+ if (h == -1)
+ h = av_rescale(w, inlink->h, inlink->w);
+
+ if (w > INT_MAX || h > INT_MAX ||
+ (h * inlink->w) > INT_MAX ||
+ (w * inlink->h) > INT_MAX)
+ av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
+
+ outlink->w = w;
+ outlink->h = h;
+
+ /* TODO: make algorithm configurable */
+ scale->sws = sws_getContext(inlink ->w, inlink ->h, inlink ->format,
+ outlink->w, outlink->h, outlink->format,
+ SWS_BILINEAR, NULL, NULL, NULL);
+
+ av_log(ctx, AV_LOG_INFO, "w:%d h:%d fmt:%s\n",
+ outlink->w, outlink->h, avcodec_get_pix_fmt_name(outlink->format));
+
+ avcodec_get_chroma_sub_sample(outlink->format, &scale->hsub, &scale->vsub);
+
+ scale->input_is_pal = inlink->format == PIX_FMT_PAL8 ||
+ inlink->format == PIX_FMT_BGR4_BYTE ||
+ inlink->format == PIX_FMT_RGB4_BYTE ||
+ inlink->format == PIX_FMT_BGR8 ||
+ inlink->format == PIX_FMT_RGB8;
+
+ return !scale->sws;
+}
+
+static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
+{
+ ScaleContext *scale = link->dst->priv;
+ AVFilterLink *outlink = link->dst->outputs[0];
+ AVFilterPicRef *outpicref;
+
+ outpicref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
+ outpicref->pts = picref->pts;
+ outlink->outpic = outpicref;
+
+ av_reduce(&outpicref->pixel_aspect.num, &outpicref->pixel_aspect.den,
+ (int64_t)picref->pixel_aspect.num * outlink->h * link->w,
+ (int64_t)picref->pixel_aspect.den * outlink->w * link->h,
+ INT_MAX);
+
+ scale->slice_dir = 0;
+ avfilter_start_frame(outlink, avfilter_ref_pic(outpicref, ~0));
+}
+
+static void draw_slice(AVFilterLink *link, int y, int h)
+{
+ ScaleContext *scale = link->dst->priv;
+ int out_h;
+ AVFilterPicRef *cur_pic = link->cur_pic;
+ uint8_t *data[4];
+
+ if (!scale->slice_dir) {
+ if (y != 0 && y + h != link->h) {
+ av_log(scale, AV_LOG_ERROR, "Slices start in the middle!\n");
+ return;
+ }
+ scale->slice_dir = y ? -1 : 1;
+ scale->slice_y = y ? link->dst->outputs[0]->h : y;
+ }
+
+ data[0] = cur_pic->data[0] + y * cur_pic->linesize[0];
+ data[1] = scale->input_is_pal ?
+ cur_pic->data[1] :
+ cur_pic->data[1] + (y>>scale->vsub) * cur_pic->linesize[1];
+ data[2] = cur_pic->data[2] + (y>>scale->vsub) * cur_pic->linesize[2];
+ data[3] = cur_pic->data[3] + y * cur_pic->linesize[3];
+
+ out_h = sws_scale(scale->sws, data, cur_pic->linesize, y, h,
+ link->dst->outputs[0]->outpic->data,
+ link->dst->outputs[0]->outpic->linesize);
+
+ if (scale->slice_dir == -1)
+ scale->slice_y -= out_h;
+ avfilter_draw_slice(link->dst->outputs[0], scale->slice_y, out_h);
+ if (scale->slice_dir == 1)
+ scale->slice_y += out_h;
+}
+
+AVFilter avfilter_vf_scale = {
+ .name = "scale",
+ .description = "Scale the input video to width:height size and/or convert the image format.",
+
+ .init = init,
+ .uninit = uninit,
+
+ .query_formats = query_formats,
+
+ .priv_size = sizeof(ScaleContext),
+
+ .inputs = (AVFilterPad[]) {{ .name = "default",
+ .type = CODEC_TYPE_VIDEO,
+ .start_frame = start_frame,
+ .draw_slice = draw_slice,
+ .min_perms = AV_PERM_READ, },
+ { .name = NULL}},
+ .outputs = (AVFilterPad[]) {{ .name = "default",
+ .type = CODEC_TYPE_VIDEO,
+ .config_props = config_props, },
+ { .name = NULL}},
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-11 16:30:56 +0000