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Athletic l&c
September 4th, 2018, 16:27
I don't mean to complain at a producer colleague :). I'm just not so good at video resolution and such stuff and sometimes gets so disappointed when buying videos.

I wonder what you out there think is "High resolution". My last video is 1280 x 720, 19 minutes long and the filesize is 2148 mb. I don't write this one out as "High resolution". Is it H Res?

One site produce videos and also announce them as High resolution. But I always gets disappointed about the picture quality after buying them. His videos are usually 426 x 240 (he doesn't write that out) or 854 x 480 and for example 14 minutes and 577 mb. Can this be high resolution?

When can you call a video H Res? And what does that involve when it comes to size and so on? Am I making my video files unnecessary big? What is good enough?

Thank's for helping me clearing this out.

dp
September 4th, 2018, 17:34
Considering that even mobile phones have 4K cameras these days, I wouldn't even call 1080p "high resolution". 720p should be the absolute minimum in my opinion, 1080p is what I expect, and anything above is a bonus.

Far
September 4th, 2018, 23:04
Resolution itself doesn't matter much until you watching video on 50-inch TV. As Dp mentioned above, now many phones have "4K" cameras, action-cams too, but thats not true 4K because size of sensor is very small. Few years ago Nokia presents phone with 41-mexapixel camera...lol, any DSLR cam shoots better with their 10-12Mp sensor))

720p is enouth in my opinion for screens up to 20-24 inch
1080p is enouth for most of screens, exept newest big TVs
lower resolutions is for Youtube only

Athletic l&c
September 5th, 2018, 21:53
Thanks for your answers. But is it only the size (1280 x 720) etc that decides how big the files will be? When I edit and then make the videos I can go for H264 and choose "Mbps 16" What is this Mbps? I thought it was this that made the videos more clear and with better picture... It definitely seems to have an effect on the file size...

dp
September 5th, 2018, 23:26
All modern video formats use so-called "lossy" compression, meaning that you can sacrifice image quality to reduce the file size. Many image formats do the same thing, including JPEG, the most common format of them all. For example, compare the two attached images. Both are the same resolution (800 x 533), but one is only 6 kB in file size while the other is over 500 kB. I think you can guess which of the two images is the smaller one. ;)

The "Mbps" number you mention is the bitrate, a very important parameter for the picture quality. It stands for "Megabits per second" and it tells the video encoder how many bits of data it is allowed to use per second of video. The higher the bitrate, the higher the quality will be. However, due to diminishing returns, you don't want to set it to the highest possible setting, that will just waste disk space and network bandwidth. The appropriate bitrate depends on the resolution - the higher the resolution, the higher the bitrate must be to get acceptable quality. For VOD (downloadable video files, as opposed to streaming), it is always better to ask the encoder to aim for constant quality rather than constant bitrate. In other words, you allow the encoder to change the bitrate based on what's going on in the video, thus maintaining constant quality.

Athletic l&c
September 8th, 2018, 21:06
All modern video formats use so-called "lossy" compression, meaning that you can sacrifice image quality to reduce the file size. Many image formats do the same thing, including JPEG, the most common format of them all. For example, compare the two attached images. Both are the same resolution (800 x 533), but one is only 6 kB in file size while the other is over 500 kB. I think you can guess which of the two images is the smaller one. ;)

The "Mbps" number you mention is the bitrate, a very important parameter for the picture quality. It stands for "Megabits per second" and it tells the video encoder how many bits of data it is allowed to use per second of video. The higher the bitrate, the higher the quality will be. However, due to diminishing returns, you don't want to set it to the highest possible setting, that will just waste disk space and network bandwidth. The appropriate bitrate depends on the resolution - the higher the resolution, the higher the bitrate must be to get acceptable quality. For VOD (downloadable video files, as opposed to streaming), it is always better to ask the encoder to aim for constant quality rather than constant bitrate. In other words, you allow the encoder to change the bitrate based on what's going on in the video, thus maintaining constant quality.

Thanks a lot for your detailed explanation. So I think I stick to what I do right now when editing videos. No one had complained abut the picture quality, so far, and I hope that means they are ok. As long as there is enough "room" to upload them I think big files that means better quality is preferred from most buyers:)