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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m trying to implement a vorbis decoder, and am having some trouble getting it to work with stereo vorbis data.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It’s giving me some PCM output which is roughly right, but it has artefacts.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I think it’s most likely something to do with my handling of floor decode/curve synthesis. My first thoughts are that I’m handling the submap number/floor mapping incorrectly;<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m interested in finding out about this from the documentation;<o:p></o:p></p>
<h5><span class="cmtt-12">(</span><span class="titlemark">4.3.2. floor curve decode)<o:p></o:p></span></h5>
<h5><span class="cmtt-12"><span style="font-weight:normal">[submap_number] </span>
</span><span style="font-weight:normal">= element <span class="cmtt-12">[i] </span>
of vector [vorbis_mapping_mux] <o:p></o:p></span></h5>
<p class="MsoNormal">What happens if during mapping decoding vorbis_mapping_mux is empty because
<span class="cmtt-12">vorbis_mapping_submaps was 1? Do both channels use the single submap in this case?<o:p></o:p></span></p>
<p class="MsoNormal"><span class="cmtt-12"><o:p> </o:p></span></p>
<p class="MsoNormal"><span class="cmtt-12">Also, I’m noticing that in this same situation, I’m getting a vorbis_floor_count of 2. What’s the purpose of the second floor in this case, if both channels are referencing the first floor?<o:p></o:p></span></p>
<p class="MsoNormal"><span class="cmtt-12"><o:p> </o:p></span></p>
<p class="MsoNormal"><span class="cmtt-12">Thanks,</span><o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><b>Adam Bradley<o:p></o:p></b></p>
<p class="MsoNormal"><span style="color:#595959">Audio Systems Developer<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#595959">Jagex Games Studio<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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