Does larger GOP length affects video?

[Anonymous543]

https://youtu.be/nFGmb8Z2zLw

Anyone watch this video which I found on youtube

In the end of video he says larger GOP will cause damage frames

But I don't think so it will make damage in video frames

I think it will just make video hard to seek


that damage caused by missing i-frames or because of long GOP lengths or any other reason?

[VoodooFX]

In the end of video he says larger GOP will cause damage frames

He doesn't say that. That would be nonsense.

[Anonymous543]

Agreed ,but he compared 2 videos in end
With GOP 12 and 120

GOP 12 video looked good and
GOP 120 video looked damaged

That's why am getting confused,
Does increasing GOP make video frames damaged?

[ProWo]

The longer the GOP, the fewer frames with a complete picture. If in the course of the GOP a frame is defective, then the following frames referring to the defective one can no longer be displayed correctly and the display is defective until the next full frame (IDR frame).
Errors in the stream are therefore more easily noticed in longer GOPs.

[VoodooFX]

GOP 12 video looked good and
GOP 120 video looked damaged

Both GOP 12 and GOP 120 videos there look "damaged". He says "if there are damage".

Does increasing GOP make video frames damaged?

Any GOP doesn't make any damage.

[jagabo]

Whether you get a corrupt picture depends on how the player seeks. Many players have a "fast seek" option where they seek to the nearest I-frame. That will give no corruption but seeks may be several seconds off from the requested frame. Other players will seek to the nearest keyframe before the requested frame invisibly, then decode all the frames up to the requested frame (also invisibly), then finally start showing the video at the requested frame. These will not show a corrupt picture but there will be a delay until all those frames have been decoded, sometimes several seconds depending on the GOP size, the frame size, and the speed of the decoding. Finally, some players will seek directly to the requested frame and start decoding. These will deliver a corrupt picture until the next I-frame is encountered.

[Anonymous543]

Oh

[jagabo]

And, of course, errors in the file or transmission may result in corruption. That corruption will usually continue until the next keyframe. That is one reason why streaming digital video uses short GOPs (typically 1 to 2 seconds between keyframes). Also, since those types of transmissions can be picked up at any time (viewers don't have to start watching at the start of the program) you don't want long delays between the time you switch to a channel and when you start seeing the program.

[Anonymous543]

Do you know what is default GOP length of libx264?
Default GOP length will make video corruption?

[Cornucopia]

No specific length will MAKE corruption.

[jagabo]

Do you know what is default GOP length of libx264?

250 frames.

Default GOP length will make video corruption?

GOP size doesn't cause corruption.

[VoodooFX]

Obvious troll

[lordsmurf]

Troll? Eh, maybe not.

Longer GOP also cause higher decode resources. So corruption can appear in that process, even if no corruption exists.