mp4 will not play in HU
mp4 will not play in HU
1990 Eunos Roadster in Mariner DU blue
Cobalt cat back, Decat pipe, 15in Red Rota GT3 alloys, Toyo tyres, Lowered on Coil overs, Red anti roll bars, 14degree timing mod, white dash kit, illuminated side marker lights,
Halo ring headlights, OEM windblocker, Bluetooth streaming HU, Blue leather handbrake and gear lever gaitor, Centre brake/tail light mod, Blue velour door cards, Polished cam cover, Polished front strut bar, 4xheadrest speakers, JDM floor mats, Suede semi dish steering wheel,
So confusing, as steve said a mp3 is a mp3, but not in the case of mp4, We need someone to explain this subject in greater depth as I am sure me, steve and partiban are not the only ones that know nothing about it.
1990 Eunos Roadster in Mariner DU blue
Cobalt cat back, Decat pipe, 15in Red Rota GT3 alloys, Toyo tyres, Lowered on Coil overs, Red anti roll bars, 14degree timing mod, white dash kit, illuminated side marker lights,
Halo ring headlights, OEM windblocker, Bluetooth streaming HU, Blue leather handbrake and gear lever gaitor, Centre brake/tail light mod, Blue velour door cards, Polished cam cover, Polished front strut bar, 4xheadrest speakers, JDM floor mats, Suede semi dish steering wheel,
The file is as Steve says, a 'container' file format, which means it's just a vessel for other data formats. It's difficult to explain but think of the file as actually being a folder with 2 other files inside it, one for the audio and one for the video. So an AVI file can have different kinds of video and audio in it (the video can be DivX, Xvid, MPEG, h.264 (the same format used in MP4) or even old formats like indeo or RLE or the godawful MJPEG, while the audio can be AC3, MP3, WAV etc). The AVI format just bundles the audio and video data together and tells the player how to keep the two in sync. This obviously makes for a lot of combinations of formats - you could have an AVI file with Xvid video and MP3 audio, for which the player device would have to be able to demux (decode the 2 separate streams) AVI file format, as well as having a CODEC for Xvid video and MP3 audio. You could then have another AVI file which looks and sounds identical, but the video is in h.264 format and the audio is in WAV format. The player would use the same demux process to split the data inside the AVI file into video and audio, but would then have to load CODECs for h.264 and WAV in order to play the file back.
Is everyone keeping up?
My understanding was that for file formats to be certified MPx their format has to have been fixed by the moving picture experts group. I would have thought you would therefore have less combinations of audio and video format inside an MP4 file. Due to how MPEG compression works you then get bitrate and resolution differences, so it could be that your player is only smart enough to keep up with lower bitrates or particular video resolutions (i.e. something could that could play back standard definition MP4 but not high definition). However like I said I'm not that well versed in MP4 as I stopped mucking about with this stuff a few years ago.Oh and in order to maintain my status as chief pedant, CODEC = ENcoder/decoder
I don't know a great deal about MP4 but if Steve's right then it works a lot like AVI files, which I do know a lot about :lol:
The file is as Steve says, a 'container' file format, which means it's just a vessel for other data formats. It's difficult to explain but think of the file as actually being a folder with 2 other files inside it, one for the audio and one for the video. So an AVI file can have different kinds of video and audio in it (the video can be DivX, Xvid, MPEG, h.264 (the same format used in MP4) or even old formats like indeo or RLE or the godawful MJPEG, while the audio can be AC3, MP3, WAV etc). The AVI format just bundles the audio and video data together and tells the player how to keep the two in sync. This obviously makes for a lot of combinations of formats - you could have an AVI file with Xvid video and MP3 audio, for which the player device would have to be able to demux (decode the 2 separate streams) AVI file format, as well as having a CODEC for Xvid video and MP3 audio. You could then have another AVI file which looks and sounds identical, but the video is in h.264 format and the audio is in WAV format. The player would use the same demux process to split the data inside the AVI file into video and audio, but would then have to load CODECs for h.264 and WAV in order to play the file back.
Is everyone keeping up? My understanding was that for file formats to be certified MPx their format has to have been fixed by the moving picture experts group. I would have thought you would therefore have less combinations of audio and video format inside an MP4 file. Due to how MPEG compression works you then get bitrate and resolution differences, so it could be that your player is only smart enough to keep up with lower bitrates or particular video resolutions (i.e. something could that could play back standard definition MP4 but not high definition). However like I said I'm not that well versed in MP4 as I stopped mucking about with this stuff a few years ago.
Oh and in order to maintain my status as chief pedant, CODEC = ENcoder/decoder
1990 Eunos Roadster in Mariner DU blue
Cobalt cat back, Decat pipe, 15in Red Rota GT3 alloys, Toyo tyres, Lowered on Coil overs, Red anti roll bars, 14degree timing mod, white dash kit, illuminated side marker lights,
Halo ring headlights, OEM windblocker, Bluetooth streaming HU, Blue leather handbrake and gear lever gaitor, Centre brake/tail light mod, Blue velour door cards, Polished cam cover, Polished front strut bar, 4xheadrest speakers, JDM floor mats, Suede semi dish steering wheel,
Thanks toxo, sounds like a bit of a dark hole this mp4 lark. such a shame because electrical goods are sold as mp4 compatible, but you try to get them to work, just comes up "invalid file format", so that head unit, that pocket mp4 player and even my tv can not do what it says on the tin.
1990 Eunos Roadster in Mariner DU blue
Cobalt cat back, Decat pipe, 15in Red Rota GT3 alloys, Toyo tyres, Lowered on Coil overs, Red anti roll bars, 14degree timing mod, white dash kit, illuminated side marker lights,
Halo ring headlights, OEM windblocker, Bluetooth streaming HU, Blue leather handbrake and gear lever gaitor, Centre brake/tail light mod, Blue velour door cards, Polished cam cover, Polished front strut bar, 4xheadrest speakers, JDM floor mats, Suede semi dish steering wheel,
I agree Phil, it's pretty misleading when you buy stuff that says "will play MP4s", because that is pretty meaningless. You will find it plays some MP4 files and not others (because they've used different codecs).
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IS200 Turbo project now just about complete ! See my thread here and leave your comments.
Now running standalone Syvecs ECU and no stock ECU !
steviewevie
20-09-2017, 09:50 AM #24Yep, MP4 files are kinda like AVI files, in that they're a container format.
I agree Phil, it's pretty misleading when you buy stuff that says "will play MP4s", because that is pretty meaningless. You will find it plays some MP4 files and not others (because they've used different codecs).
IS200 Turbo project now just about complete ! See my thread here and leave your comments.
Now running standalone Syvecs ECU and no stock ECU !
steviewevie Yep, MP4 files are kinda like AVI files, in that they're a container format.
I agree Phil, it's pretty misleading when you buy stuff that says "will play MP4s", because that is pretty meaningless. You will find it plays some MP4 files and not others (because they've used different codecs).
The better the playback machine the more MP4 formats it will be able to read. These cheap Chinese units are cheap for a reason!!
"Life's goal is not to arrive safely at the grave in a well preserved body. But, rather to skid in sideways........
totally worn out and broken, shouting 'Holy ****, WHAT A RIDE!'"
FirebirdPhil
22-09-2017, 05:02 AM #25steviewevie Yep, MP4 files are kinda like AVI files, in that they're a container format.
I agree Phil, it's pretty misleading when you buy stuff that says "will play MP4s", because that is pretty meaningless. You will find it plays some MP4 files and not others (because they've used different codecs).
The better the playback machine the more MP4 formats it will be able to read. These cheap Chinese units are cheap for a reason!!
"Life's goal is not to arrive safely at the grave in a well preserved body. But, rather to skid in sideways........
totally worn out and broken, shouting 'Holy ****, WHAT A RIDE!'"
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