Bitrate question about converting to m2ts format

[mulliganman]

Hello. I have been using Video to Video Conversion program and was wondering if I should be trying to make the bitrates of the incoming file match the output of the new file if possible. My incoming files have been lossless AVI's and the output is a .m2ts file for bluray burning. When I select .m2ts file as what I convert to within the program it automatically sets the bitrate to 2500. Like I said the bitrate of the original is higher. I sincerely apologize if this is a "dumb" question, but am very much a newbie to this stuff.

[Cornucopia]

You (usually) want to make your outputs tailored to the best that can be gotten from the intended playback devices.

If your sources are truly lossless avis they will likely be ~10x-20x the size (and bitrate) - maybe more - you would end up with going to the usual destinations (dvd, bd, avchd, streaming-ready mp4 & mkv). M2ts is ~one of those destination formats (it's what makes up the essence of bd & avchd).

So, obviously you cannot and should not keep the files the same rate as your sources. They are geared towards different purposes (lossless for robustness in editing & archiving, lossy for compactness & convenience in playback). The point of lossy encoding is to throw away a whole lot of the image without being very noticeable to humans (but this makes them "fragile" and hinders their further use in editing).

Scott

[mulliganman]

You (usually) want to make your outputs tailored to the best that can be gotten from the intended playback devices.

If your sources are truly lossless avis they will likely be ~10x-20x the size (and bitrate) - maybe more - you would end up with going to the usual destinations (dvd, bd, avchd, streaming-ready mp4 & mkv). M2ts is ~one of those destination formats (it's what makes up the essence of bd & avchd).

So, obviously you cannot and should not keep the files the same rate as your sources. They are geared towards different purposes (lossless for robustness in editing & archiving, lossy for compactness & convenience in playback). The point of lossy encoding is to throw away a whole lot of the image without being very noticeable to humans (but this makes them "fragile" and hinders their further use in editing).

Scott

Thanks for weighing in! This is what I thought. For original recording if done via screen recording, I would still want the highest bitrate attainable for the original recording correct?

[Cornucopia]

CORRECT!

Save that ~losslessly, edit it. Save the edited master ~losslessly, then convert to your final destination format. Make sure you have plenty of drive space to archive your sources and/or your edited master (because you may very well want to revisit them).

Scott

[mulliganman]

CORRECT!

Save that ~losslessly, edit it. Save the edited master ~losslessly, then convert to your final destination format. Make sure you have plenty of drive space to archive your sources and/or your edited master (because you may very well want to revisit them).

Scott

Thanks! Do you have a recommendation on a lossless codec that is excellent but doesn't bog down your system and result in laggy recordings? Right now, I've got Lagaraith, and HuffyUV to choose from (but if I missing a beter alternative I can pick it up).

[Cornucopia]

Those are good ones, but I guess that depends on your system...

Scott

[mulliganman]

Those are good ones, but I guess that depends on your system...

Scott

This is what I have with an I5 processor: http://downloads.dell.com/Manuals/all-products/esuprt_desktop/esuprt_inspiron_desktop/...uide_en-us.pdf

[Cornucopia]

Using lossless media puts more stress on the storage end of the system rather than on the processor end. Do you have internal or external drives (the ones that are the target for Video)? Are they DEDICATED to only video use (or are they part of the boot/system drive)? Are they very fast (7200rpm, 10000rpm, 15000rpm HDDs, or SSDs)? Are you using RAID or not? What is the bus type? - IDE, SATA1, SATA2, SATA3?...

These influence more whether your PC can fetch & send data reliably in time (since it's doing MUCH less decoding/encoding than with lossy formats).

Scott

[mulliganman]

Using lossless media puts more stress on the storage end of the system rather than on the processor end. Do you have internal or external drives (the ones that are the target for Video)? Are they DEDICATED to only video use (or are they part of the boot/system drive)? Are they very fast (7200rpm, 10000rpm, 15000rpm HDDs, or SSDs)? Are you using RAID or not? What is the bus type? - IDE, SATA1, SATA2, SATA3?...

These influence more whether your PC can fetch & send data reliably in time (since it's doing MUCH less decoding/encoding than with lossy formats).

Scott

I purchased this to use exclusively for the storage: http://www.amazon.com/gp/product/B00FRHTSK4?psc=1&redirect=true&ref_=oh_aui_detailpage_o06_s00

I am only going to use it for video and thought I could replace it when full with another or something else if there is a better option. Does this help at all?

[mulliganman]

Using lossless media puts more stress on the storage end of the system rather than on the processor end. Do you have internal or external drives (the ones that are the target for Video)? Are they DEDICATED to only video use (or are they part of the boot/system drive)? Are they very fast (7200rpm, 10000rpm, 15000rpm HDDs, or SSDs)? Are you using RAID or not? What is the bus type? - IDE, SATA1, SATA2, SATA3?...

These influence more whether your PC can fetch & send data reliably in time (since it's doing MUCH less decoding/encoding than with lossy formats).

Scott

If I should be using something else for saving video recording by screen capture or video recording by video ripping then please share? I will certainly take a look...

[Cornucopia]

Could be good, could be a mixed bag. 2TB is good (for modest editing filesize needs), but it's listed as a "backup" drive, which usually puts it in the slower internal speed category (5400RPM or 7200RPM, not so good). Obviously not SSD. You only have 1, so no RAID. Internally (inside its enclosure) it is probably SATA, and USB3.0 should be good, but you'd have to guarantee that it isn't actually using USB2.0 which would greatly hamper its ability as an external. The whole Cloud thing is wasted for video.

Do some large filesize full-drive read+write data transfer tests to see what real-world transfer speeds you're getting out of this (there are apps you can DL, but make sure they're not doing the usual small-size tests, which don't translate well to video use). For slightly-compressed lossy HD stuff, you'd need minimum consistent R+W transfer of ~20MB/sec (~160Mbps), for many lossless formats it would be more like ~50MB/sec (~400Mbps), uncompressed would be double-to-quadruple that. Multiply that by the # of simultaneous layers you'd be using to edit/composite with, and possibly whether you'd be wanting to do realtime rendering (READ and WRITE together), and that's the minimum consistent, long-term data rate you'll need.

BTW, use NTFS for your filesystem to avoid 4GB barriers.

Scott

[mulliganman]

Could be good, could be a mixed bag. 2TB is good (for modest editing filesize needs), but it's listed as a "backup" drive, which usually puts it in the slower internal speed category (5400RPM or 7200RPM, not so good). Obviously not SSD. You only have 1, so no RAID. Internally (inside its enclosure) it is probably SATA, and USB3.0 should be good, but you'd have to guarantee that it isn't actually using USB2.0 which would greatly hamper its ability as an external. The whole Cloud thing is wasted for video.

Do some large filesize full-drive read+write data transfer tests to see what real-world transfer speeds you're getting out of this (there are apps you can DL, but make sure they're not doing the usual small-size tests, which don't translate well to video use). For slightly-compressed lossy HD stuff, you'd need minimum consistent R+W transfer of ~20MB/sec (~160Mbps), for many lossless formats it would be more like ~50MB/sec (~400Mbps), uncompressed would be double-to-quadruple that. Multiply that by the # of simultaneous layers you'd be using to edit/composite with, and possibly whether you'd be wanting to do realtime rendering (READ and WRITE together), and that's the minimum consistent, long-term data rate you'll need.

BTW, use NTFS for your filesystem to avoid 4GB barriers.

Scott

I used Parkdale. Inside the Quick Access with a 4 GB file option chosen gives me the following results:

Sequential Write Speed: 119.8 MByte/sec. Random QD32: 1137.5kByte/sec, 284.4 IOPS, 3.52 ms

Sequential Read Speed: 124.8 MByte/sec. Random QD32: 323.7 kByte/sec, 80.9 IOPS, 12.36 ms



I also did a File Access test with it on a 57.8 Gigabite file recording with the lossless Lagarith codec. This was the results:

Read speed: 119.8 MByte/sec

Write speed: 108.2 MByte/sec.

Does this help?

[Cornucopia]

Yeah. According to that, as long as you don't have extra/rogue processes bogging you down, you should be OK.

Scott