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  1. Many CD and even DVD players support:
    • Audio CD. Same PCM as wavesound, just with MODE1/Mode2Form1 error correction, as known from CD-ROM's/data CD-R(W).
    • DVD-Video players support PCM audio but no wavesound? And only MP3 CDs, no DVDs with MP3 files. (The 2004's DV-RW250 from my early childhood is meant for recording, and is excellent in that area, but can not read files (MP3,WMA,JPG) on DVDs? Yes, it CAN read VIDEO_TS.IFO, even on DVD+RW, despite the manual claims that DVD plus is unsupported. The DVR-R07 (equivalent of Pioneer DVR-107) inside the DV-RW250 supports it however, so does the device itself.
    • CD/DVD players play WMA, a heavily patented and restricted format. But no trace about the open-source embracing XiPH!
    • SunPlus DVD players support mpg/mp2/mp4 among PCM audio, but no wavesound.wav files? That's embarrassing! MPEG-4 and PCM playback must support wavesound files with ease! Lazy programmers? Wavesound is nearly CDDA, just with CD-ROM-like error correction and occasionally different formats than 44.1kHz/Stereo 2ch/16bit. MP4 bitrate is easily sufficient for 5.1 WAV audio.
    • PNG files should also soon be openable. Rockbox but also Transcend MP870 with stock firmware supports many, many formats. Even FLV and SWF. But no dual-pass video decoding.
    • Several DVD players read MP3 files on CDs, but no MP2/MPG/DAT as file, despite of the same video format that VCD/SVCD/DVD also have.

    Is that not a bit irrational?
    • WMA but no Vorbis playback.
    • DVD-Video with PCM, MP3 file, MP4 sometimes, but no WAV file playback.
    • MP3 files, MPEG2 video, but no MPG/MO2 files.

    I would appreciate an explanation.
    I am just curious about these irrational limitations.
    Last edited by TechLord; 4th Jan 2018 at 18:30. Reason: More accurate description.
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  2. Member Cornucopia's Avatar
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    PCM isn't the SAME as wavesound (WAV). Wav is a container that can include LPCM, ADPCM, mp3, float, much more. The PCM in Audio CD (which, BTW, is a pure raw stream, not in a container) is big-endian (motorola style), while the PCM when used in WAV is little-endian (intel style). Otherwise, they are compatible & transferable without loss. But not the same.

    Look, there are many things that the chipset of the players COULD do, but from the standpoint of the manufacturers and their core producers & consumers, the point of building these pieces of equipment is to do the core applications: AudioCD, DVD-Video, BD, etc. If you want "general purpose", that's what the point of a generic drive and computer are for.
    The logic for these devices almost universally works like this: check disc type, check application type, change options within the application. Then, as an AFTERTHOUGHT, you may have support for additional combinations of elements that are already supported. Then, if it is trying to also be more general than that, it MIGHT have capability for commonly provided consumer formats.
    And this is where WMA/WMV comes in, because it was offered (pushed?) by MS as a deal for them to support it. Not because consumers told manufacturers what they want. It has always been PRODUCER-DRIVEN, not consumer-driven. It has to reach a large critical mass acceptance before it is considered an option (mp3 is an example).
    Which is why you don't see WAV support in any form except in Car Audio players, or general media players. Or PNG, except in Digital photo screens. Manufacturers are wary of adding opensource capability to anything except devices that are themselves built on opensource (as are most general media players), as TO THEM, it smacks of accepting piracy, and they would never want to piss off producers. Took a long time for MKV to be supported. Divx (licensed from producer) was supported officially, and since Xvid was compatible, that is the only reason Xvid enjoyed as much support as it has.

    So, for example, your SunplusDVD player accepts mpg/mp2/mp4? Sure, because it already accepts DVD VOBs, which is a form of MPG, and MP2 is part of the DVD spec, and MP4 is in the same family as MPG-PS & TS so is not a stretch at all. Yet NONE of those use a WAV container, and there is NO other common consumer format that uses as its base the WAV container which would be a reason to include support for the container on its own.

    So, not irrational at all. Makes sense.
    Not my preference, nor clearly yours, but we aren't the decisionmakers nor influencers when it comes to manufacturing options.

    You are also inaccurate WRT error correction on AudioCDs vs CDROMs/DVDs. AudioCDs and CDXA Mode2form2 (incl. VCD mpeg tracks) include 2 forms of error correction. CD-Roms (mode1 or mode2/form1) & DVD/BD include those 2 plus an additional one (IOW, 3), as well as include more accurate sector seeking. Which is why the tradeoff of sector size.

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