![]() So seeking to frame 599 of a 600 frame GOP requires decompressing 599 frames before the frame can be shown to you. With long GOPs and large frame sizes that can take quite a while. When seeking to the middle of a GOP, to reconstruct that frame the decoder must first decompress the keyframe before the requested frame, then add in all the changes for the B and P frames up to the requested frame. ![]() That distance between I frames is the GOP size, or keyframe interval (keyint in x264). Ie, the encoded video says "this frame is the same as the last frame, except for these changes." Eventually the encoder will create another I frame followed by a bunch more P and B frames. So in a talking head shot on a static background one frame will encode the entire picture (an I frame, or keyframe) but the next several frames (P and B frames) will only include the changes due to the moving lips/head of the speaker. In case you are wondering, most high compression codecs get a lot of their compression by not repeating parts of the picture that don't change from frame to frame. Here's a mediainfo for the vid but this issue is for most of the mp4 i try to edit: Does anyone have any fixes for this, setting I need to change, or maybe another open source editor I can use? I want to keep everything the same as source except decreasing the bitrate. The video isn't out of sync but it just seems to need to buffer every time I try to seek. If I try to seek maybe 20 mins ahead, there's ~5 sec pause before playing. ![]() If I try to seek 30 secs ahead, there's probably a 1 sec pause before the video actually starts playing. Not sure if seeking is the technical term but what I mean is going to a specific time in the video. And I noticed that most of the MP4s I edit has issues with seeking the video. I tried to decrease the bitrate of a MP4 in Handbrake using pretty much default settings for everything beside the avg bitrate with turbo & 2-pass.
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