VIdeo Storage

[danroll]

How much video (with sound) can be stored on a 1gb memory card from a digital video recorder.

obviously a higher video quality will affect the size of the file. is there somewhere i can find out???

[Ethel]

Not much - I can get one film (2 hours) of high quality video on a 4.7gb dvd disk - more low quality

[danroll]

that depends on the level of compression you are using and the format which the video is in. I'm talking about using memory cards as the primary method of storage when filming with a DV camera. then i could whip it out of the camera put it in my computer and upload it onto the system.

What i want to know really is this the most efficient way to store video?

[pug100]

Hi Dan,
I'm afraid the best way to record and store video is still video tape.
All professionals still use tape and spend ages digitising into computer format for editing then recoring it back onto tape for transmission.

As Ethel states you won't get much quality video on 1GB. You can of course compress it (like they do on mobiles ipods etc) but you will lose the quality.

[pug100]

I just foun this article which gives the amount of data you get with a dv camera - 1GB will give you 4 mins.

Video compression
DV uses DCT intraframe compression at a fixed bitrate of 25 megabits per second (25.146 Mbit/s), which, when added to the sound data (1.536 Mbit/s), the subcode data, error detection, and error correction (approx 8.7 Mbit/s) amounts in all to roughly 36 megabits per second (approx 35.382 Mbit/s) or one Gigabyte every four minutes. At equal bitrates, DV performs somewhat better than the older MJPEG codec, and is comparable to intraframe MPEG-2. (Note that many MPEG-2 encoders for real-time acquisition applications only use intraframe compression [I-frames only], but not interframe compression [P and B frames].) DCT compression is lossy, and sometimes suffers from artifacting around small or complex objects such as text.

[danroll]

cheers guys

[ACtheTROLL]

It's not so much where it's from .... although 1Gb won't go far. It's more ... where it's going

a vid shown on a HD 47" screen needs to be better quality (and thus bigger) than the vid required for viewing on an iPod or phone

and even then ... it depends how much the quality matters

For me (from my trusty tivo - recorded at medium quality [I know - define medium!]) the full size - runs at about 1Gb per hour. and is perfectly ok on our telly (in fast action ... there is a little blockyness - but I'm ok with that)

I regularly put 5 full films onto a single DVD using shrink and burn - and can get 5 family guys on a single CD

... on my archos mp3/4 player ... I can get a full film into less than 100Mb

It's all relative .... as with still cameras ... a single RAW pic can easily take 20 Mb - the resulting jpg can be as little as 20-30Kb and still be quite acceptable