Re: exhale - Open Source USAC encoder
Reply #72 – 2020-05-03 19:21:20
• BITRATE TABLE : CLASSICAL MUSIC ONLY (91 discs, over 100 hours)ENCODER PRESET | BITRATE | STEREO | FULL SET | MONO LOW BITRATE HIGH BITRATE | (91 CD) | (3 CD) (4 CD) (3 CD) ------------------------------------------------------------------------------------ FLAC CUEtools -8 | 580.2 kbps | 467.7 kbps 264.0 kbps 1028.7 kbps ------------------------------------------------------------------------------------ exhale 1.0.3 x64 mode 2 | 80.6 kbps | 85.7 kbps 54.3 kbps 96.0 kbps exhale 1.0.3 x64 mode 3 | 99.3 kbps | 100.7 kbps 62.8 kbps 115.0 kbps exhale 1.0.3 x64 mode 4 | 110.5 kbps | 110.0 kbps 67.5 kbps 126.7 kbps exhale 1.0.3 x64 mode 5 | 131.2 kbps | 123.7 kbps 77.3 kbps 145.3 kbps • Small comparison between exhale mode #3 and other tools at similar target ------------------------------------------------------------------------------------- (VBR settings ~96 kbps) | BITRATE | (stereo) | FULL SET | MONO LOW BITRATE HIGH BITRATE ENCODER PRESET | (91 CD) | (3 CD) (4 CD) (3 CD) ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- OGG libVorbis I 20150105 q2 | 85.9 kbps | 72.0 kbps 76.5 kbps 106.3 kbps MP3 LAME 3.100 V6 | 89.6 kbps | 60.3 kbps 52.5 kbps 115.7 kbps AAC iTunes 7.10.9.0 tvbr45 | 96.8 kbps | 54.7 kbps 81.0 kbps 99.7 kbps AAC FAAC 1.29.9.2 -q 120 | 97.4 kbps | 73.7 kbps 61.0 kbps 158.3 kbps exhale 1.0.3 x64 mode 3 | 99.3 kbps | 100.7 kbps 62.8 kbps 115.0 kbps OPUS 1.3.1 x64 vbr 96 | 103.4 kbps | 78.7 kbps 104.5 kbps 117.3 kbps AAC fdkaac 4.0.0 LC mode 3 | 110.6 kbps | 66.0 kbps 94.0 kbps 108.0 kbps In this table you can see that exhale seems quite unefficient with my monophonic records. _______About these 91 discs: I have a very large library with classical music only. Very large means insanely large (the kind of playlist that last several years). Everything is encoded to FLAC (CUETools -8) and the average bitrate for 44.1 KHz/16bit is 581 kbps. For obvious reason I can’t encode the whole library to get average bitrate for different encoders/settings. Testing means selecting. Thus my plan was to reduce this huge library to something easier to handle. My first though was to find myself 50 to 100 albums that end with an average bitrate at 581 kbps. But I finally tried something different. These last 20 years many labels released countless large boxset (All Mozart, All Karajan, Greatest Concerto, 150 years of <choose city> Orchestra, 100 greatest recordings from <label>, etc…). I tried to find one or two boxset and get my ~580 kbps. Bingo! Deutsche Grammophon released a 111 Years anniversary boxset of 55 discs ; Harmonia Mundi a 29 discs anniversary boxset. With both sets I reached 581 kbps (579 kbps on an Excel table). Every classical subgenres and every musical periods are represented. There are three mono albums and recordings from beginning of stereo to 2007. It seems that I found my reference for future tests. To these 84 CD I also add extreme albums: those which need very little bitrate in lossless (<300 kbps in stereo) and those which requires more than 1000 kbps (which is really rare with classical music). These extremes might be useful to spot how other VBR encoders handles these kind of signals. Consequently I add 4 low bitrate discs and 3 high bitrate discs to the 84 first CD.The average bitrate for this 91 CD test collection is 582 kbps (weighted by duration) of 580.2 kbps (average values with Excel) , values that are very close to my entire library (581 kbps).