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jruggle · 17th July 2006, 23:17

Ok, I can finally reply!

To answer a few questions...

aften_g is not really different from aften in any significant way. The "aften_g" executable has debugging symbols, where "aften" does not. The size of the binary is larger for aften_g, but it is useful in finding problems in the code.

DRC is something that will be tricky to add. I do wish I had access to a good reference encoder to compare with. Maybe getting some DVD's and making a simple parser would give some clues as to how to calculate it properly.

24/32/float wav files will be supported sometime soon. It won't be that hard...I just have to rework the API a bit.

Filtering...I agree with adding a filter for LFE and DC, but not for bandwidth. That is effectively taken care of by excluding the highest MDCT coefficients. The only advantage I can see is maybe a smoother transition band.

I'm sorry that the site was down for a few days...I was out-of-town and it seems a power flicker reset my web server.

VBR and containers: As mentioned by others, it can be done in AVI the same way as with MP3. Also, I just found a place in the spec where it implies that VBR should be supported in MPEG-TS. There are two sets of bitrate codes for the audio stream descriptor. One set is for exact bit rate, while the other is for bit rate upper limit. I have gotten VBR to "work" in avi, mpeg-ps, mpeg-ts, and matroska. Decoding support will probably still be very limited though. I am really hoping that DVD players will support it. I would guess yes since most of the manufacturers probably paid for a Dolby-certified decoder so they could put the logo on the player.

Thanks for the GUI kurtnoise13. I don't have Windows, so could someone post a screenshot somewhere? I'm just curious.

I might have an old version of Aften I wrote in Java lying around on my computer somewhere. If so, I could easily write a cross-platform GUI for that. For the record, I don't care much for Java when it comes to mathematical stuff because of the lack of unsigned types and pointer control, but it's wonderful for quick-n-easy graphical interfaces...and card games

.

If I forgot anything or there are any other questions, ask away.

-Justin

17th July 2006, 23:17	#36 \| Link
jruggle Registered User Join Date: Jul 2006 Posts: 276	Ok, I can finally reply! To answer a few questions... aften_g is not really different from aften in any significant way. The "aften_g" executable has debugging symbols, where "aften" does not. The size of the binary is larger for aften_g, but it is useful in finding problems in the code. DRC is something that will be tricky to add. I do wish I had access to a good reference encoder to compare with. Maybe getting some DVD's and making a simple parser would give some clues as to how to calculate it properly. 24/32/float wav files will be supported sometime soon. It won't be that hard...I just have to rework the API a bit. Filtering...I agree with adding a filter for LFE and DC, but not for bandwidth. That is effectively taken care of by excluding the highest MDCT coefficients. The only advantage I can see is maybe a smoother transition band. I'm sorry that the site was down for a few days...I was out-of-town and it seems a power flicker reset my web server. VBR and containers: As mentioned by others, it can be done in AVI the same way as with MP3. Also, I just found a place in the spec where it implies that VBR should be supported in MPEG-TS. There are two sets of bitrate codes for the audio stream descriptor. One set is for exact bit rate, while the other is for bit rate upper limit. I have gotten VBR to "work" in avi, mpeg-ps, mpeg-ts, and matroska. Decoding support will probably still be very limited though. I am really hoping that DVD players will support it. I would guess yes since most of the manufacturers probably paid for a Dolby-certified decoder so they could put the logo on the player. Thanks for the GUI kurtnoise13. I don't have Windows, so could someone post a screenshot somewhere? I'm just curious. I might have an old version of Aften I wrote in Java lying around on my computer somewhere. If so, I could easily write a cross-platform GUI for that. For the record, I don't care much for Java when it comes to mathematical stuff because of the lack of unsigned types and pointer control, but it's wonderful for quick-n-easy graphical interfaces...and card games . If I forgot anything or there are any other questions, ask away. -Justin