diff options
Diffstat (limited to 'libswscale')
| -rw-r--r-- | libswscale/utils.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/libswscale/utils.c b/libswscale/utils.c index 27819854e4..2111fc2a62 100644 --- a/libswscale/utils.c +++ b/libswscale/utils.c @@ -914,7 +914,17 @@ av_cold int sws_init_context(SwsContext *c, SwsFilter *srcFilter, SWS_SINC | SWS_SPLINE | SWS_BICUBLIN); - if (!i || (i & (i - 1))) { + + /* provide a default scaler if not set by caller */ + if (!i) { + if (dstW < srcW && dstH < srcH) + flags |= SWS_GAUSS; + else if (dstW > srcW && dstH > srcH) + flags |= SWS_SINC; + else + flags |= SWS_LANCZOS; + c->flags = flags; + } else if (i & (i - 1)) { av_log(c, AV_LOG_ERROR, "Exactly one scaler algorithm must be chosen\n"); return AVERROR(EINVAL); |