3rd of 5 factorized patches; supersedes
https://patchwork.ffmpeg.org/patch/16272/
scale_eval.c | 69 --------------
vf_scale.c | 286
+++++++++++++++++++++++++++++++++++++++++++++++++++++++----
2 files changed, 271 insertions(+), 84 deletions(-)
2a3ae4ce4e91893fddb020485e6936c82894eb81
0003-avfilter-scale-separate-exprs-parse-and-eval.patch
From 00b54948b88ae60aa3ab7c158b98e55cb8b967d3 Mon Sep 17 00:00:00 2001
From: Gyan Doshi <ffm...@gyani.pro>
Date: Thu, 12 Dec 2019 22:54:31 +0530
Subject: [PATCH 3/5] avfilter/scale: separate exprs parse and eval
Will allow adding animation support.
@@ -566,19 +746,87 @@ static int process_command(AVFilterContext
*ctx, const char *cmd, const char *ar
char *res, int res_len, int flags)
{
ScaleContext *scale = ctx->priv;
- int ret;
+ AVFilterLink *outlink = ctx->outputs[0];
+ char *old_w_str, *old_h_str;
+ AVExpr *old_w_pexpr, *old_h_pexpr;
+ int ret, w = 0, h = 0;
+ const char scale2ref = ctx->filter == &ff_vf_scale2ref;
+ const char *const *names = scale2ref ? var_names_scale2ref :
var_names;
+
+ w = !strcmp(cmd, "width") || !strcmp(cmd, "w");
+ h = !strcmp(cmd, "height") || !strcmp(cmd, "h");
+
+ if (w || h) {
- if ( !strcmp(cmd, "width") || !strcmp(cmd, "w")
- || !strcmp(cmd, "height") || !strcmp(cmd, "h")) {
+ if (w) {
+ old_w_str = av_strdup(scale->w_expr);
+ if (!old_w_str)
+ return AVERROR(ENOMEM);
+ old_w_pexpr = scale->w_pexpr;
+ scale->w_pexpr = NULL;
+ }
- int old_w = scale->w;
- int old_h = scale->h;
- AVFilterLink *outlink = ctx->outputs[0];
+ if (h) {
+ old_h_str = av_strdup(scale->h_expr);
+ if (!old_h_str)
+ return AVERROR(ENOMEM);
+ old_h_pexpr = scale->h_pexpr;
+ scale->h_pexpr = NULL;
+ }
av_opt_set(scale, cmd, args, 0);
+
+ if (w) {
+ ret = av_expr_parse(&scale->w_pexpr, scale->w_expr,
+ names,
+ NULL, NULL, NULL, NULL, 0, ctx);
+ if (ret < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Cannot parse width
expression: '%s'\n", scale->w_expr);
+ av_opt_set(scale, "w", old_w_str, 0);
+ av_free(old_w_str);
+ scale->w_pexpr = old_w_pexpr;
+ return ret;
+ }
+ }
+
+ if (h) {
+ ret = av_expr_parse(&scale->h_pexpr, scale->h_expr,
+ names,
+ NULL, NULL, NULL, NULL, 0, ctx);
+ if (ret < 0) {
+ av_log(ctx, AV_LOG_ERROR, "Cannot parse height
expression: '%s'\n", scale->h_expr);
+ av_opt_set(scale, "h", old_h_str, 0);
+ av_free(old_h_str);
+ scale->h_pexpr = old_h_pexpr;
+ return ret;
+ }
+ }
+
if ((ret = config_props(outlink)) < 0) {
- scale->w = old_w;
- scale->h = old_h;
+
+ if (w) {
+ av_opt_set(scale, "w", old_w_str, 0);
+ av_free(old_w_str);
+ av_expr_free(scale->w_pexpr);
+ scale->w_pexpr = old_w_pexpr;
+ }
+ if (h) {
+ av_opt_set(scale, "h", old_h_str, 0);
+ av_free(old_h_str);
+ av_expr_free(scale->h_pexpr);
+ scale->h_pexpr = old_h_pexpr;
+ }
+ av_log(ctx, AV_LOG_ERROR, "Command failed. Continuing
with existing parameters.\n");
+ return ret;
+ }
