HD bitrates & 1.8" HDD support

[nalooti]

Hi,

I was wondering if 1.8" hard disk drives have enough data bitrate (at 4200 rpm) to sustain playing a HD movie (e.g. an external HDD connected to a DVD/DivX player with USB port).

Obviously the answer is not simple and depends on many parameters but it should be possible to build a worst case scenario:
USB 1.1 bandwidth (12 Mbps), Max disk platters data bitrate (? hard to find specs), Mpeg2 HD bandwidth (15 Mbps ???).
For HD contents, there are obviously many factors; one is the algorithm Mpeg2/4 . Assuming Mpeg4 needs lower bitrate for the same quality, Mpeg2 is the worst case. But the other factor is resolution on which depends the final bitrate in ANY compression standard.

The questions are:
1/ Do you know any list comparing different compression standards based on the type of contents (SD, HD, resolutions, ...) and the codec standard (Mpeg2, Mpeg4 AVC, etc.) ?

2/ Did you ever use a 1.8" HDD for playing video files ? If yes what is the max resolution/bitrate that the HDD supported?

many thanks
nalooti

[mats.hogberg]

Not that I know the answer, but bitrate is the only video related factor to take into account.
Not compression format. Not resolution. Just bitrate (audio + video).

/Mats

[nalooti]

Not that I know the answer, but bitrate is the only video related factor to take into account.
Not compression format. Not resolution. Just bitrate (audio + video).

/Mats

I agree that bitrate is the final factor in order to check if the HDD is able to support the playback (including its interface and data rates).
However in the world of contents you often see the resolution and compression standard rather than the final bitrate. So in some way you have to deduce the bitrate from these.

[jagabo]

The speed of the USB 1.1 port will be the limiting issue. 1.8 inch drives can sustain between 10 and 20 megabytes per second. Most Divx/DVD players with USB 1.1 ports have poor USB handling and can only get 0.5 megabytes per second from the USB port. They will start to stutter with bitrates over 4000 kbps.

Also note that most Divx/DVD players will not play high def anything. They are typically limited to 720x480 30 fps or 720x576 25 fps -- standard def DVD frames sizes and frame rates.

[jman98]

nalooti - I would suggest that in the future that you NOT say "HD" at all. This abbreviation could mean "high definition" or "hard disk". Not long ago we had a post here where a guy say "HD" and he received a lot of responses about recording high definition shows and then he said he meant "hard disk" and was interested in learning about hard disk recorders.

I can only assume you mean "high definition". It's a waste of time because you can count on one hand the number of DVD/Divx players there are that can play high definition Divx. The odds are that you don't have one of these players. They are VERY expensive. You'll easily pay 300 Euros or much more for such a player.

[nalooti]

The speed of the USB 1.1 port will be the limiting issue. 1.8 inch drives can sustain between 10 and 20 megabytes per second. Most Divx/DVD players with USB 1.1 ports have poor USB handling and can only get 0.5 megabytes per second from the USB port. They will start to stutter with bitrates over 4000 kbps.

I wonder if 4 Mbps is not the limit of the chipset uncompressing Mpeg2 or DivX.
If this limit comes from the USB 1.1 port then my guess was to try 1.8" drives that consumes much less current than the 2.5" ones, to see if things improve.

Also note that most Divx/DVD players will not play high def anything. They are typically limited to 720x480 30 fps or 720x576 25 fps -- standard def DVD frames sizes and frame rates.

I understand what you mean. I may be confused but some DivX/DVD players can upscale to 720p or 1080p. Now, would that mean that the electronic circuitry is ready for HiDef (since it is able to upconvert an SD stream to a HiDef one) playback??? I don't think so.
If yes then it can't play HD just because it doesn't support HD-DVD or Blueray media.

Finally, I thing the real limiting factor is the chipset bandwidth. That explains the choice of USB 1.1 port since it has ample bandwidth (12 Mbps) for SD contents

nalooti

[KBeee]

You seem to be confused about what a DVD/DivX player can do, and is doing.
Because there is upscaling on the output has no relevance to what the player will accept on the input.
A 1.1 USB port is not fast enough to display HQ video, let alone HD video, putting a slower, less power-hungry external HDD won't change this, and unless you get an expensive HD-DviX player you'll be limited to inputting/playing 720*480/576 anyway. AVC or 264 encoded video doesn't apply, because you are limited to DivX/XviD/mpeg (usually).

A USB connected HDD probably won't work at all unless it's externally powered, and formatted to FAT32. The USB standard only allows up to half an amp to power USB devices, and most DVD/DivX players seem to be much fussier than computer USB ports.
Some newer DVD/DivX players are coming with USB2 ports now, and even so they struggle to display DVD quality video, though they seem more successful with lower bitrate DivX/Xvids. They are still limited to the 720*480/576 framesize, and 4GB FAT32 limit though.