Lister player control shortcuts

[solid]

Hi.
In the lister playin video, there are button for skipping certain amount of time (defaults are 10 and 60 seconds). But, there is not a keyboard shortcut to perform the same or at least I can not find it.

Is there any way to enable shortcut for this functions?

[ghisler(Author)]

No there isn't, sorry. Any suggestions?

[Usher]

2ghisler(Author)
It's been already proposed:
viewtopic.php?p=401389&hilit=left+right#p401389

[solid]

No there isn't, sorry. Any suggestions?

Usher's proposal is just fine.

Left and right arrow are used for skipping some time. But there is not much of a consensus among popular video players which modifier keys should be used with left and right arrow for changing the amount of skipping time.

For example, VLC uses four different jump lengths, default values are 3, 10, 60 and 300 seconds. Hotkeys Shift+Right, Alt+Right. Ctrl+Right, Ctrl+Alt+Right. I find these quite cumbersome because they can be easily mixed up. Letter 'e' is used as a hotkey for frame by frame advance, but there is not and cannot be assigned a hotkey for previous frame.

Gom player uses same modifiers, but in reverse order than VLC. Ctrl+Alt is for shortest jump, Shift for longest.

Of course, all decent players have option for changing the hotkeys.

Video editing programs have different approach. There left/right arrows are always for one frame reverse/forward. Shift is a multiplier, usually ten times (frames) or one second. They also use JKL keys for navigating. K pause, L play forward, J play backwards. Tapping J or L multiplies playback speed. Holding K and pressing J or L is for moving frame by frame, holding them pressed is for slow motion.

Also typing on numpad goes to specific time, format HHMMSSFF. So typing 20000 (NumEnter to confirm) goes to two minutes, 200 goes to two seconds. Players usually omit FF, so 2 is for two seconds, 200 is two minutes. Preceding numbers with NUM+ or NUM-, jumps relative time. For example typing NUM+ 200 jumps two seconds (or minutes) ahead.

I'm writing this because TC player already has possibility for changing playback speed (although not in same steps as video editor) and a frame by frame advance.

I'm aware that video editors have completely different purpose than video players, but some of those features for moving in video are very useful and should be incorporated in video players.

I don't know how TC handles playback internally and to which extent are all those combinations are possible to implement.

For current implementation of TC player, I think Left and Right arrow should jump 10 seconds, and 60 with Shift. Further modifiers can have larger or smaller steps. Comma (,) and dot (.) can be used for frame by frame advancing. J and L can be used for moving through playback speed. K is pause, ALT+K reset to normal speed.
A question here, can the playback speed steps be changed and is the 1.5 highest possible?

[ghisler(Author)]

Left/Right arrow keys already controls the progress bar slider. My DVD recorder uses an interesting concept:
Keys 1 and 3 jump back/forward a small amount.
Keys 4 and 6 jump back/forward a medium amount.
Keys 7 and 9 jump back/forward a large amount.
But this is on a TV remote, there are far more keys on a regular keyboard, and many laptop keyboards don't have a numeric keypad at all...

[funkymonk]

Hello!

I would appreciate such shortcuts very much!

I totally understand and partially support the previous suggestions. However, in order to keep the direction keys consistent in function (horizontally for playback position, vertically for volume), here is slightly different suggestion with some more functions (inspired by VLC and others):

Left/Right –- Regular jump (10s / configurable)
Shift+Left/Right -– Long jump (60s / configurable)
Ctrl+Left/Right -– Short jump (1s / configurable)
,/. -– frame jump backward/forward
Pos1/End -– Go to first/last frame
NumBlock <hhmmss> followed by NumReturn -– Jump to time (e.g., 010203 and 10203 would go to 1:02:03)
In case no NumBlock is available, Jump to time is either not available or another key (e.g., J or F3) could open a window where the time can be entered.

Space or P -– Pause/Play
+/- -– Inc/dec playback speed
* -– Normal playback speed

Up/Down -– Volume up/down (10% / configurable)
PgUp/PgDown -– Volume max/min
M -- toggle mute

Return or F -- toggle full screen mode
I -- Show video media information
ESC –- Close player

Another (but probably not that important) feature could be A-B playback:
Ins/Del or A/B -- set A/B position

Please note: The keys are (or should be) located closely together so everything can be easily reached with one hand.

BR
funkymonk

[Usher]

But this is on a TV remote

Don't even try to use that. Classic phones and TV remotes use different keyboard layout than calculators and computer numpads.

Code: Select all

phone/remote  calc/pc
1  2  3       7  8  9
4  5  6       4  5  6
7  8  9       1  2  3
   0          0

[solid]

2ghisler(Author)
Thanks for implementing the shortcuts in TC10.50b1.

Is it possible to add a shortcut for 'single step back'? Opposite of key 'E'.

[ghisler(Author)]

A single step back would only be possible for audio, but would not work for most videos. Why? To compress videos more, they consist of many groups of pictures: Usually an I-Frame, which is essentially a still image like JPG, followed by many differential frames which just store the difference to that I-frame (simplified). These groups of pictures can be several 100 frames long!

Video is made to play forward, so it's easy to calculate a frame from a previous frame. But to go back one frame, you may need to go back 100 frames to the previous I-frame, and then decode all the intermediate frames until one less than where you were before! That's also the reason why seeking manually to a new position can take several seconds.

[solid]

Yes, that is true for interframe compressed codecs like mpeg or h264/5.
There are intraframe compressed codecs like Prores, DNX, Cineform etc. where each frame is coded individually, so the video is just a bunch of individual pictures just stitched together.

Nevertheless, I don't see why going one frame backwards is different than going n seconds backwards (or forward) or just clicking anywhere in the time slider. The pointer can fall on any P/B frame, so the difference from nearest I frame must be calculated anyway.

So skipping backwards 1s, 1s, 1s, or 1f, 1f, 1f from computational pov is the same.
Also it is expected in the interframe codecs that playing backward is not smooth or responsive as normal forward playback.

[ghisler(Author)]

Nevertheless, I don't see why going one frame backwards is different than going n seconds backwards (or forward) or just clicking anywhere in the time slider.

It's not different, it's just too slow to be usable! When going back, say, 60 seconds, it's OK to wait 1-2 seconds to get to the frame. But waiting that long each time you want to go back 1 frame would be terrible, e.g. when you need to go back 30 frames until you find the one you need. So better change one of the two "go back" buttons to e.g. one second, and then go forward to the desired frame.

[solid]

On my computer there is not waiting, all skips are instant. It is 3rd generation i5 with built in GPU, so nothing special.
At least for FHD videos coded with h264/5. There is a short delay on 4K videos, but even those on modern computers are insignificant.

Going back a second then going forward many frames is not usable scenario when comparing adjacent frames in case when motion is studied or moment of the cut.

Please add a hotkey for one frame backwards.
At least for consistency, step forward is the only function that don't have its counterpart (play/pause, jump forward/backwards, slower/faster, vol. up/down, zoom +/-)