[FFmpeg-devel] [RFC] ignore invalid user-supplied width/height

[Reimar Döffinger]

Hello,
most video codecs will figure out a width/height themselves or fail
if they can't.
So IMO it is better not to fail for invalid values in avcodec_open but
instead just ignore the values by using the "default" of 0.
Otherwise applications would have to manually check the values with
av_check_image_size if they want the video to remain playable even
if the container values were corrupted.
Any objections?

Index: libavcodec/utils.c
===================================================================
--- libavcodec/utils.c  (revision 24961)
+++ libavcodec/utils.c  (working copy)
@@ -485,10 +485,15 @@
     else if(avctx->width && avctx->height)
         avcodec_set_dimensions(avctx, avctx->width, avctx->height);
 
+    if ((avctx->coded_width || avctx->coded_height)
+        && av_check_image_size(avctx->coded_width, avctx->coded_height, 0, avctx) < 0) {
+        av_log(avctx, AV_LOG_WARNING, "ignoring invalid width/height values\n");
+        avctx->coded_width  =
+        avctx->coded_height = 0;
+    }
+
 #define SANE_NB_CHANNELS 128U
-    if (((avctx->coded_width || avctx->coded_height)
-        && av_check_image_size(avctx->coded_width, avctx->coded_height, 0, avctx))
-        || avctx->channels > SANE_NB_CHANNELS) {
+    if (avctx->channels > SANE_NB_CHANNELS) {
         ret = AVERROR(EINVAL);
         goto free_and_end;
     }