If you shoot video footage on your smartphone, for example, chances are it’s being compressed immediately and will be compressed even more throughout your transfer, editing, exporting and uploading process. This is done by using a specific compression algorithm to reduce the total number of bits needed for each frame (or image) contained in the video clip. Video compression is the process of reducing the overall file size of a video file or clip. However, when done with the wrong software or in the wrong way, video compression can sometimes corrupt a file and make it unusable - so you want to make sure you’re using the proper software and following the right steps. When done properly, a good video compressor can reduce the size of a video file to nearly 1,000x smaller than the original. Not sure what a ZIP file’s all about? That’s video compression. Wanna send a video file over email? You need compression. In today’s modern digital video production process, video compression is quite regular and necessary because the majority of video files which you’ll deal with need to be reduce to make your workflows possible. How to compress a video in iOS and on Macs.Watch our video tutorial on how to compress a video.What is a codec, and why do I need to know?.Do I have to compress a video in order to share it?.The real question is not what we think ought to look better, but whether an unbiased or disinterested viewer can, without any cues, tell any difference. In the case of sports or action, perhaps not much different, or perhaps 1920x1080 60p 28mbps won't offer much perceivable advantage over 1280x720 60p 15mbps. Would footage shot with the same camera, and streamed over Vimeo, look any different? In the case of flowers and fenceposts, probably not. Someone at Luminous Landscape did a similar test and found no advantage.Īnother worthy test would be to compare AVCHD1 (humble 60i at 17mbps or less) to AVCHD2 (28mbps). An extra recorder connected to an HDMI feed is an expensive encumberance. Not to bicker with "pros" who need decompressed video for complex edit effects, most people don't edit at all, and even enthusiasts can do everything or more than time permits to edit AVCHD as-is. Some people pay for high speed super bandwidth, but most cannot play HD video at all without considerable buffer time, which is tantamount to repelling many viewers from seeing a video at all. The Ninja 2 version looks a bit worse.īut, honestly, the use of any high bitrate codec is moot if everything must be recompressed in the end and streamed at 5mps or even lower. The better clips are the ones you say came from the camera, using its standard AVCHD2 compression. See any glaring differences from the Vimeo versions or the originals? Looks like AVCHD 60p does a really nice job, and gives you really small files. I was holding the camcorder and Ninja with one hand, but that also challenges the codecs. The scenes have a lot of red flowers and a lot of detail so a challenge for any codec. They are the same length - high bitrates have a cost. Or, if you are a member of Vimeo, you can download the originals. You can open two windows and run the two videos simultaneously. The Ninja2 Apple/Avid high-bitrate/high sampling version of the same scenes from the uncompressed output is here: The camcorder-produced AVCHD 60p at 28Mbps version is here: The edited videos were then separately uploaded to Vimeo. The AVCHD 108060p clips were edited and combined without recompression. To maximize quality I edited and converted the Apple Pro Res 422 60i clips to Avid DNxHD 60i (145Mbps), which also uses 10 bits per channel with 4:2:2 chroma subsampling, in Sony Vegas Pro. Notice that the bitrate is not only much higher, but also there is more information obtained on color (chroma). This is a codec the pros use to edit with. I shot with the Ninja and the camcorder simultaneously, the Ninja getting its signal from the uncompressed 108060i put out by the camcorder (and which bypassess the internal processor) and using Apple Pro Res 422 (145Mbps, yes, 145 Mbps), which uses 10 bits per channel with 4:2:2 chroma subsampling to compress the uncompressed signal. The camcorder has a clean HDMI signal and uses AVCHD compression, 1080 progressive 60fps, 8 bits per channel with 4:2:0 chroma sampling. I borrowed a colleague's Ninja 2 - a video recorder - to see if it produced video that was superior to what my camcorder could produce using its own processor. Using a really high-quality, very high bitrate codec that the pros use (and is really easy to edit) to compare? Wouldn't it be great if we could take videos at 108060p using AVCHD and simultaneously shoot the same scenes Do they, given this cost, deliver good video? 108060p AVCHD video clips are difficult to play and hellish to edit.
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