/*
- * copyright (c) 2007 Bobby Bingham
+ * Copyright (c) 2007 Bobby Bingham
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
*/
#include "avfilter.h"
+#include "libavutil/avstring.h"
+#include "libavutil/eval.h"
+#include "libavutil/mathematics.h"
#include "libavutil/pixdesc.h"
#include "libswscale/swscale.h"
+static const char *var_names[] = {
+ "PI",
+ "PHI",
+ "E",
+ "in_w", "iw",
+ "in_h", "ih",
+ "out_w", "ow",
+ "out_h", "oh",
+ "a",
+ "hsub",
+ "vsub",
+ NULL
+};
+
+enum var_name {
+ VAR_PI,
+ VAR_PHI,
+ VAR_E,
+ VAR_IN_W, VAR_IW,
+ VAR_IN_H, VAR_IH,
+ VAR_OUT_W, VAR_OW,
+ VAR_OUT_H, VAR_OH,
+ VAR_A,
+ VAR_HSUB,
+ VAR_VSUB,
+ VARS_NB
+};
+
typedef struct {
struct SwsContext *sws; ///< software scaler context
int hsub, vsub; ///< chroma subsampling
int slice_y; ///< top of current output slice
int input_is_pal; ///< set to 1 if the input format is paletted
+
+ char w_expr[256]; ///< width expression string
+ char h_expr[256]; ///< height expression string
} ScaleContext;
static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
ScaleContext *scale = ctx->priv;
const char *p;
- scale->flags = SWS_BILINEAR;
- if (args){
- sscanf(args, "%d:%d", &scale->w, &scale->h);
- p= strstr(args,"flags=");
- if(p) scale->flags= strtoul(p+6, NULL, 0);
- }
+ av_strlcpy(scale->w_expr, "iw", sizeof(scale->w_expr));
+ av_strlcpy(scale->h_expr, "ih", sizeof(scale->h_expr));
- /* 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;
+ scale->flags = SWS_BILINEAR;
+ if (args) {
+ sscanf(args, "%255[^:]:%255[^:]", scale->w_expr, scale->h_expr);
+ p = strstr(args,"flags=");
+ if (p) scale->flags = strtoul(p+6, NULL, 0);
}
- if (scale->w == -1 && scale->h == -1)
- scale->w = scale->h = 0;
return 0;
}
AVFilterLink *inlink = outlink->src->inputs[0];
ScaleContext *scale = ctx->priv;
int64_t w, h;
+ double var_values[VARS_NB], res;
+ char *expr;
+ int ret;
+
+ var_values[VAR_PI] = M_PI;
+ var_values[VAR_PHI] = M_PHI;
+ var_values[VAR_E] = M_E;
+ var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
+ var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
+ var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
+ var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
+ var_values[VAR_A] = (float) inlink->w / inlink->h;
+ var_values[VAR_HSUB] = 1<<av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
+ var_values[VAR_VSUB] = 1<<av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
+
+ /* evaluate width and height */
+ av_expr_parse_and_eval(&res, (expr = scale->w_expr),
+ var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx);
+ scale->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
+ if ((ret = av_expr_parse_and_eval(&res, (expr = scale->h_expr),
+ var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+ goto fail;
+ scale->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
+ /* evaluate again the width, as it may depend on the output height */
+ if ((ret = av_expr_parse_and_eval(&res, (expr = scale->w_expr),
+ var_names, var_values,
+ NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
+ goto fail;
+ scale->w = res;
+
+ w = scale->w;
+ h = scale->h;
+
+ /* sanity check params */
+ if (w < -1 || h < -1) {
+ av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
+ return AVERROR(EINVAL);
+ }
+ if (w == -1 && h == -1)
+ scale->w = scale->h = 0;
if (!(w = scale->w))
w = inlink->w;
scale->sws = sws_getContext(inlink ->w, inlink ->h, inlink ->format,
outlink->w, outlink->h, outlink->format,
scale->flags, NULL, NULL, NULL);
+ if (!scale->sws)
+ return AVERROR(EINVAL);
+
+ return 0;
- return !scale->sws;
+fail:
+ av_log(NULL, AV_LOG_ERROR,
+ "Error when evaluating the expression '%s'\n", expr);
+ return ret;
}
static void start_frame(AVFilterLink *link, AVFilterBufferRef *picref)
outpicref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
avfilter_copy_buffer_ref_props(outpicref, picref);
+ outpicref->video->w = outlink->w;
+ outpicref->video->h = outlink->h;
- outlink->outpic = outpicref;
+ outlink->out_buf = 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,
+ av_reduce(&outpicref->video->pixel_aspect.num, &outpicref->video->pixel_aspect.den,
+ (int64_t)picref->video->pixel_aspect.num * outlink->h * link->w,
+ (int64_t)picref->video->pixel_aspect.den * outlink->w * link->h,
INT_MAX);
scale->slice_y = 0;
{
ScaleContext *scale = link->dst->priv;
int out_h;
- AVFilterBufferRef *cur_pic = link->cur_pic;
+ AVFilterBufferRef *cur_pic = link->cur_buf;
const uint8_t *data[4];
if (scale->slice_y == 0 && slice_dir == -1)
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);
+ link->dst->outputs[0]->out_buf->data,
+ link->dst->outputs[0]->out_buf->linesize);
if (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.",
+ .description = NULL_IF_CONFIG_SMALL("Scale the input video to width:height size and/or convert the image format."),
.init = init,
.uninit = uninit,