Proposal for “Stepping faster/smooth”

[EFuggerth]

Recently your team successfully corrected a nasty disturbance I encountered: "Flashing sequence of pictures" instead of smooth video resulted... (https://avidemux.org/smif/index.php?topic=18296.new;topicseen#new)
I wonder if you can be enticed to offer further comfort for the user.
My present proposal is about the stepping.
For this to do you presently offer 3 options: "fast", (jumping 1 minute) "medium" (jumping ~0.64sec), "finest" (jumping 0.04sec, i.e. by the picture/frame). [These convert as 1"medium"=12"finest" and 1"fast"=120"medium".] The problem is the proportion/length, which leads to too many clicking to be done on fine-tuning.
Finding a better balance to equalize the lengths of the step-options could be one way.
A still better way, however, would be to introduce a program-step that differentiates between a click and a button hold down. In the latter case the tuning is allowed to proceed until the button is released, by automatically repeating the clicking-action – just as is the case in holding a key in a word-processor.

[eumagga0x2a]

My present proposal is about the stepping.
For this to do you presently offer 3 options: "fast", (jumping 1 minute) "medium" (jumping ~0.64sec), "finest" (jumping 0.04sec, i.e. by the picture/frame). [These convert as 1"medium"=12"finest" and 1"fast"=120"medium".]

The only way to seek in a video which is really fast is seeking to keyframes (this is probably what you describe as "medium" as it matches approximately the usual GOP length in MPEG-2 streams). Seeking not to keyframes is relatively slow because you have to go to the last keyframe before the target and decode from that point until the wanted PTS (presentation timestamp) pops out. I.e. the distance from the keyframe to the wanted time determines how long a seek takes.

Your question is more about the granularity of seek. You seem to be unaware of the 1 second (Left/Right+Shift), 2 seconds (Left/Right+Ctrl) and 4 seconds (Left/Right+Shift+Ctrl) steps present in Avidemux since very long time already. As time-based seeks involve decoding various numbers, sometimes even hundreds of frames, they may be very slow, especially when seeking backward in a video with long GOPs.

A still better way, however, would be to introduce a program-step that differentiates between a click and a button hold down. In the latter case the tuning is allowed to proceed until the button is released, by automatically repeating the clicking-action – just as is the case in holding a key in a word-processor.

This is exactly how it works: holding down a key or a group of keys belonging to a keyboard shortcut fires repeated calls of an action assigned to the key or the keyboard shortcut, the frequency specified in the system keyboard settings. Avidemux just doesn't swap the corresponding action depending on how long the keys were pressed, which I deem a good thing. Repeated commands just don't make sense / can't work right for slow time-based seeks.

The most practicable way to seek for a particular scene with unknown time is dragging the slider, then going to the previous keyframe (maybe repeating this step couple of times for streams with short GOPs), then starting playback and stopping as close before the desired position as possible, finally using frame-stepping forward.

[eumagga0x2a]

A still better way, however, would be to introduce a program-step that differentiates between a click and a button hold down.

Oops, I've got now that you want auto-repeat enabled for some navigation buttons. This makes a lot of sense for the buttons to seek to the previous / next keyframe and to advance to the next frame. Going to the previous frame in auto-repeat mode won't work in a satisfactory way for HD stuff except of on top-notch hardware with working full hardware-accelerated decoding and display, but the lack thereof would be even more confusing IMHO.

Implemented by [Qt/gui] Enable auto-repeat for some navigation buttons, should be available in future nightlies.

[EFuggerth]

I must apologize for not discovering your prompt reply, but no automatic message was received about, and amid my other tasks to attend I clearly forgot this otherwise not too vital issue.
Reading it now, I have definitely profited from it, thanks.
Really, never knew before the 1,2,4 sec moving-options activated by Left/Rigth+Shift etc.
From now on, I will rely on them.
[This of my coming back is due to another question, put separate as "New version (2.7.5) encumbers multitasking.]
February 20, 2020   EF

[eumagga0x2a]

No emails are sent out on new posts by default in this forum (which is a good thing IMHO).