avfilter: rename scale.c,h to scale_eval

scale.c is too generic; scale_eval is more representative

1 files changed, 48 insertions, 0 deletions

diff --git a/libavfilter/scale_eval.h b/libavfilter/scale_eval.h
new file mode 100644
index 0000000000..fceb023fec
--- /dev/null
+++ b/libavfilter/scale_eval.h
@@ -0,0 +1,48 @@
+/*
+ * 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
+ */
+
+#ifndef AVFILTER_SCALE_EVAL_H
+#define AVFILTER_SCALE_EVAL_H
+
+#include "avfilter.h"
+
+/**
+ * Parse and evaluate string expressions for width and height. Upon success,
+ * ff_scale_adjust_dimensions must be called with evaluated width and height
+ * to obtain actual target dimensions.
+ *
+ * Returns 0 upon success, negative value if one of the expressions could
+ * not be parsed or if NaN was the result of their evaluation.
+ */
+int ff_scale_eval_dimensions(void *ctx,
+    const char *w_expr, const char *h_expr,
+    AVFilterLink *inlink, AVFilterLink *outlink,
+    int *ret_w, int *ret_h);
+
+/**
+ * Transform evaluated width and height obtained from ff_scale_eval_dimensions
+ * into actual target width and height for scaling. Adjustment can occur if one
+ * or both of the evaluated values are of the form '-n' or if
+ * force_original_aspect_ratio is set.
+ *
+ * Returns 0.
+ */
+int ff_scale_adjust_dimensions(AVFilterLink *inlink,
+    int *ret_w, int *ret_h,
+    int force_original_aspect_ratio, int force_divisible_by);
+#endif