shithub: libvpx

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Fixed incorrect use of compute_qdelta()

This function expects real Q values as inputs
not index values.

The use-age her impacts the Q chosen for force key
frames. Though this is a bug fix I have not yet verified
whether following the bug fix the q multiplier value used is
correct.

Change-Id: I49f6da894d90baeb1e86c820c335f02dc80d3b66

--- a/vp9/encoder/vp9_onyx_if.c

+++ b/vp9/encoder/vp9_onyx_if.c

@@ -2735,8 +2735,13 @@

     // the maximum key frame interval. Here force the Q to a range

     // based on the ambient Q to reduce the risk of popping

     if (cpi->this_key_frame_forced) {

-      const int qindex = cpi->last_boosted_qindex;

-      const int delta_qindex = compute_qdelta(cpi, qindex, qindex * 0.75);

+      int delta_qindex;

+      int qindex = cpi->last_boosted_qindex;

+      double last_boosted_q = vp9_convert_qindex_to_q(qindex);

+

+      delta_qindex = compute_qdelta(cpi, last_boosted_q,

+                                    (last_boosted_q * 0.75));

+

       cpi->active_best_quality = MAX(qindex + delta_qindex, cpi->best_quality);

     }