[FFmpeg-devel] FFmpeg bug fixing event starts today!!!

[Carl Eugen Hoyos]

Robert Swain <robert.swain <at> gmail.com> writes:

> Today is the beginning of what I believe is our first bug fixing (and
> documentation) event.

AC3 decoding depends on SSE being activated or not.
How to reproduce:
Enable ac3 decoding tests in regresssion.sh:
Index: tests/regression.sh
===================================================================
--- tests/regression.sh (revision 17221)
+++ tests/regression.sh (working copy)
@@ -391,8 +391,8 @@
 if [ -n "$do_ac3" ] ; then
 do_audio_encoding ac3.rm "" -vn
 # gcc 2.95.3 compiled binaries decode ac3 differently because of missing SSE
support
-#do_audio_decoding
-#$tiny_psnr $pcm_dst $pcm_ref 2 1024 >> $logfile
+do_audio_decoding
+$tiny_psnr $pcm_dst $pcm_ref 2 1024 >> $logfile
 fi

 if [ -n "$do_g726" ] ; then

configure with --disable-sse (and without) and compare the results of
make codectest:
SSE:
+++ tests/data/vsynth.regression        2009-02-14 11:27:20.000000000 +0100
@@ -177,6 +177,9 @@
 stddev: 4394.71 PSNR: 23.46 bytes:  1053352/  1058444
 aefe11ab5067621a1c674859d6413891 *./tests/data/a-ac3.rm
 98203 ./tests/data/a-ac3.rm
+39d5646cba5a6cfedfd58845e6df3c06 *./tests/data/ac3.vsynth.out.wav
+stddev:10496.20 PSNR: 15.90 bytes:  1056812/  1058444
+stddev: 4631.51 PSNR: 23.00 bytes:  1055788/  1058444
 39878597b1d65cce473639a7d8c93b02 *./tests/data/a-g726.wav
 24279 ./tests/data/a-g726.wav
 888f2f016e608d044a1bacbca5497ed2 *./tests/data/g726.vsynth.out.wav

disable-SSE:
@@ -177,6 +177,9 @@
 stddev: 4394.71 PSNR: 23.46 bytes:  1053352/  1058444
 aefe11ab5067621a1c674859d6413891 *./tests/data/a-ac3.rm
 98203 ./tests/data/a-ac3.rm
+0db338cbeeb5b1b011837930a5d31511 *./tests/data/ac3.vsynth.out.wav
+stddev:10496.34 PSNR: 15.90 bytes:  1056812/  1058444
+stddev: 4631.55 PSNR: 23.00 bytes:  1055788/  1058444
 39878597b1d65cce473639a7d8c93b02 *./tests/data/a-g726.wav
 24279 ./tests/data/a-g726.wav
 888f2f016e608d044a1bacbca5497ed2 *./tests/data/g726.vsynth.out.wav

Carl Eugen