On Tue, 18 Oct 2016, Michael Niedermayer wrote:

On Sun, Oct 16, 2016 at 10:12:17PM +0200, Marton Balint wrote:

On Sun, 16 Oct 2016, Marton Balint wrote:

Signed-off-by: Marton Balint <c...@passwd.hu>
---
tests/fate/filter-audio.mak | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/tests/fate/filter-audio.mak b/tests/fate/filter-audio.mak
index 9c6f7cd..d376f25 100644
--- a/tests/fate/filter-audio.mak
+++ b/tests/fate/filter-audio.mak
@@ -279,6 +279,13 @@ fate-filter-hdcd-detect-errors: CMD = md5 -i $(SRC) -af 
hdcd -f s24le
fate-filter-hdcd-detect-errors: CMP = grep
fate-filter-hdcd-detect-errors: REF = detectable errors: [1-9]

+FATE_AFILTER-$(call FILTERDEMDECENCMUX, LOUDNORM, AAC, AAC, PCM_S16LE, 
PCM_S16LE) += fate-filter-loudnorm-simple
+fate-filter-loudnorm-simple: SRC = $(SAMPLES)/aac/sintel.aac
+fate-filter-loudnorm-simple: CMD = ffmpeg -t 30 -i $(SRC) -af loudnorm=i=-23 
-f s16le -ar 44100 -
+fate-filter-loudnorm-simple: REF = $(SAMPLES)/filter/loudnorm-simple.pcm
+fate-filter-loudnorm-simple: CMP = oneoff
+fate-filter-loudnorm-simple: CMP_UNIT = s16
+

This patch needs two files in the fate samples:

The audio part of the Sintel movie, as a source, because I wanted to
test with a real world example, with proper length. And the
reference file. Sources can be generated like this:

wget http://media.xiph.org/sintel/sintel-master-st.flac
ffmpeg -i sintel-master-st.flac -codec aac -b 96k fate-suite/aac/sintel.aac
ffmpeg -t 30 -i fate-suite/aac/sintel.aac -af loudnorm=i=-23 -f s16le -ar 44100 
fate-suite/filter/loudnorm-simple.pcm

Due to the 96k AAC codec, sintel.aac is about 15M,

are low bitrate speech codecs unsuitable instead of aac for this ?
that would cut the size down by alot

In theory, maybe, on the other hand, we are only using the first 30 second of the sample, so if size is an issue, we can reduce it to around 500k and the fate test will still work.

Since the reference file alone is 6M, it does not seem to make too much difference if the sample is 500k, or less, so I'd prefer the normal codec. I am not sure I can give you a pure technical reasoning, the only thing I could think of is that as far as I know a speech codec is usually not good at very low or very high frequencies, but it is a good idea to test loudness measurement with all kind of frequencies, because of it's frequency dependant filters.

Regards,
Marton
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