![recording old video in m2ts format recording old video in m2ts format](https://www.magix.com/fileadmin/user_upload/SEO/videoformate-aendern/i_91aa73/seo-video-formats-convert-range-int.jpg)
In terms of aliasing, it really depends on what the camera is doing with the pixels and data. So shoot 25p as the norm, with your shutter at 1/50th, light allowing, move up to 50p and 1/100th when you think the shot warrants it (i.e when the benefit of pushing to slow mo will outweigh the higher compression at 50p) If you're render out your 50p footage to a 25p video, you'll be binning half the frames, again data rate is going to reduce to 14 Mbps, so almost half compared to 25p native. If you're using 50p to smooth out movement (by slowing it down to 25p), then your resultant data rate is going to be 14Mbps. The compression within the 50p data rate is greater, you're getting 28 Mbps out of 50 frames, as opposed to 24 Mbps over 25 frames. the difference is negligible, not something you'll notice by eye Keep it simple, both frame rates have approximately two reference frames per second. That's an awful lot of maths and figures! Short version: there is not much in it will keep shooting 50p Edited by Interceptor121 However once you then decompress and re-encode from 50p down to 25p as output you may as well loose all those benefits So in theory 50p recording is the way to go. If instead there is a lot of changes in a small time interval the format with more frames per second will result in less errors The difference is however minimal so I would conclude that if you were shooting a static subject there are no substantial differences between the two
#RECORDING OLD VIDEO IN M2TS FORMAT FULL#
If both files are produced with the same settings the 50p file has actually more information than the 25p based on the number of full frames and reference frames If I compare the two video bitrates of 22 and 26 Mbps with the additional frames it follows that there is a difference of 8.3% between the number of frames but 18.2% in terms of data rate. In general the 50p format contains more full frames. So in one second of 25p there are 25/13=1.92 full frames and in one second of 50p 2.08 in both cases with 2 reference frames The 50p have a GOP structure of M=1 N=24 so a full frame is repeated every 24 and the rest are predictionsīoth streams have the same number of reference frames in the GOP The 25p have a GOP structure of M=1 N=13 so a full frame is repeated every 13 and the rest are predictions I have done a bit of digging into the files produced I have done several tests and if I just take a snapshot of a frame I can't see any differences between the two that makes me think that unless I slow down the motion and use the extra frame the two iamges are essentially the same in quality, however if I have a fast moving scene the double frame rate should reduce motion artefacts? Edited by Interceptor121 I have read somewhere else that instead I should shoot 25p directly as there is more information in each frame however I believe this is not correct as H264 does not store full frames like PRORES or other codecs in fact the decrease in file size when compressing from 50p down to 25p is not great maybe 1-20%.Īm I doing the right thing to shoot at 50p 28 Mbps with a view of producing a 25p file or should I go directly to 25p 24Mbps? I am aware that the H264 codec uses temporal compression so my assumption was that with the same encoding settings the higher the bitrate the better. It is a pain to have multiple file formats in the same project so I have so far been shooting in 50p all the times slow motion or not.įor my next trip there won't be any macro so am looking at experimenting I am wondering if I should shoot directly in 25p and forget 50p entirely or if it is actually better to shoot at the highest bitrate. Slow motions is something I use at times for handheld macro to avoid vomiting when I watch the footage later.
#RECORDING OLD VIDEO IN M2TS FORMAT ISO#
The camera follows the 180 shutter rule at 50p so it shoots at 1/100th this gives videos a bit of a staccato feeling in certain scenes so am now thinking of dropping this to 1/50th although this gives me some challenges at time as the camera smallest aperture is f/11 and lowest ISO 160 (I shoot with a Sony RX100 II). The mainstream version is therefore the 25p. The 50fps version plays beautifully however even on a powerful quad 3.6 GHz iMac I see dropped frames. Out of the recording I create two files a 25 fps and a 50 fps version. I have since been choosing option 2 with a view of being able to slow motion the footage when required, Since a few years I have had little rigs capable of recording double frame rate videos.