Getting the animation length of a GIF

[Shaun]

Hello,

I was searching for an answer all over the internet and couldn't find any. So I will ask the question by myself:

Is it possible to determine the animation length of a GIF?

I could not find a command for that. I know that I can't just determine a framerate and count the frames to get the animation length, because the times between the frames can be different.
So what is the right way to get to the goal? :)
I would be really thankful for constructive answers.

Regards
Shaun

[snibgo]

Code: Select all

identify -verbose x.gif

For each frame, look for the "delay" entry, {ticks}x{ticks-per-seconds}, eg "7x100" means 7/100 seconds = 0.07s. Then add these up for the total duration.

Or more directly with ExifTool:

Code: Select all

exiftool -Duration x.gif
Duration                        : 6.10 s

[Shaun]

Hello,

thanks for your answer. Sadly, exiftool doesn't consider the iteration of a gif.

I tried the following command to get at least the image time delay for each frame:

Code: Select all

identify -verbose -format "Frame %s: %Tcs\n" 31_de_bf_gif_200x200.gif

In -verbose, I also found the information "Iterations". But I couldn't figure out how to output this information (to finally do some math to get the final practical duration of the gif).

The following doesn't work:

Code: Select all

identify -verbose -format "Frame %s: %Tcs | Duration: %[Iterations]\n" 31_de_bf_gif_200x200.gif

It only outputs the following:

Code: Select all

Frame 0: 30cs | Iterations:
Frame 1: 30cs | Iterations:
Frame 2: 30cs | Iterations:
Frame 3: 30cs | Iterations:
Frame 4: 30cs | Iterations:
Frame 5: 30cs | Iterations:
Frame 6: 30cs | Iterations:
Frame 7: 30cs | Iterations:

I was searching again for hours for a solution to get the duration of a gif including the loops. I can't believe nobody ever needed that information before.

[glennrp]

I haven't tried any of them, but googling for "gif duration" gives links to several applications that probably do what you want.

[fmw42]

I have no idea what iterations means. It only shows up for me in the first frame of the animation and is 0. Later frames only show the Scene number out of the total number of Scenes.

What do you think interations means? What were you looking for?

[glennrp]

What do you think interations means?

I believe it means "how many times to play the entire animation". If it is zero it means to replay the animation repeatedly forever.

Thanks Glenn. That explains why it only shows up in the first frame and for my -loop 0 animation, it shows zero.

Fred

[Shaun]

What were you looking for?

For the time, a gif animation needs to be finished, inclusive all loops.
So the time can be 0 seconds, n seconds or infinite.

but googling for "gif duration" gives links to several applications that probably do what you want.

Well, can you give me an example? As I said, I googled for hours and could'nt find any solution. Including other programs.

But well... I can't believe, that nobody found yet such solution for the mighty Image Magick?

[snibgo]

Code: Select all

convert xc: xc:black -loop 99 x.gif
identify -verbose x.gif | cGrep /i- /sIterations

Or:

Code: Select all

F:\web\im>exiftool -GIF:AnimationIterations x.gif
Animation Iterations            : 99

[Shaun]

Code: Select all

convert xc: xc:black -loop 99 x.gif
identify -verbose x.gif | cGrep /i- /sIterations

This gives me only the number of iterations...which can't even be accessed via an variable. :/ I dont know how I could continue here to get the final duration.

Code: Select all

F:\web\im>exiftool -GIF:AnimationIterations x.gif
Animation Iterations            : 99

Hm, via exiftool, I get at least also the Duration for one iteration. But how can I multiply those two values? I need a solution where I can output the final duration. So at least, I need to be able to do some math in the command line.

Thanks for your answer. :)

[glennrp]

I've pushed an update to the SVN repostory, IM6, version 14582, to add image->duration to image.h, calculate it in gif.c, and report it (if non-zero) in identify.c.
To do: calculate duration in other animation-supporting formats including MIFF, MPC, and MNG, and port to IM7.

[fmw42]

This should do it. Unix syntax

# create animation with 4 frames, delay 50 and iterations 8
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif

# get duration
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif
iterations=`convert rose.gif[0] -verbose info: | sed -n 's/^[ ]*Iterations: \([0-9]*\)*$/\1/p'`
delayArr=(`convert rose.gif -format "%T\n" info:`)
numframes=${#delayArr[*]}
duration=0
for ((i=0; i<numframes; i++)); do
duration=`convert xc: -format "%[fx:$duration + $iterations*${delayArr[$i]}]" info:`
done
echo $duration
1600

[glennrp]

This should do it. Unix syntax

# create animation with 4 frames, delay 50 and iterations 8
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif

# get duration
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif
iterations=`convert rose.gif[0] -verbose info: | sed -n 's/^[ ]*Iterations: \([0-9]*\)*$/\1/p'`
delayArr=(`convert rose.gif -format "%T\n" info:`)
numframes=${#delayArr[*]}
duration=0
for ((i=0; i<numframes; i++)); do
duration=`convert xc: -format "%[fx:$duration + $iterations*${delayArr[$i]}]" info:`
done
echo $duration
1600

More generally, we must account for the possibility that the delay is not the same for
each frame. The code that I added to gif.c does that by keeping a running
tally.

• glenn.rp> q16convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif
  glenn.rp> q16identify -verbose rose.gif | grep urat
  Duration: 1600

• glenn.rp> q16convert -delay 50 rose: rose: -delay 10 rose: rose: -loop 8 rose.gif
  glenn.rp> q16identify -verbose rose.gif | grep Duration
  Duration: 960

Glenn,

Mine does to by getting the delays from every frame (as delayArr) and looping to add them together. But a more automatic and direct way is always better. My solution was temporary until you implement yours.

Fred

[Shaun]

This should do it. Unix syntax

# create animation with 4 frames, delay 50 and iterations 8
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif

# get duration
convert -delay 50 rose: rose: rose: rose: -loop 8 rose.gif
iterations=`convert rose.gif[0] -verbose info: | sed -n 's/^[ ]*Iterations: \([0-9]*\)*$/\1/p'`
delayArr=(`convert rose.gif -format "%T\n" info:`)
numframes=${#delayArr[*]}
duration=0
for ((i=0; i<numframes; i++)); do
duration=`convert xc: -format "%[fx:$duration + $iterations*${delayArr[$i]}]" info:`
done
echo $duration
1600

Thanks! Just one little bug: The number of iterations needs to be increased by 1 do get the correct duration.

[glennrp]

Thanks! Just one little bug: The number of iterations needs to be increased by 1 do get the correct duration.

Unfortunately the word "iterations" is ambiguous. Netscape, Firefox, and ImageMagick interpret it (as commonly used
by computer programmers) to mean "number of times to play" while Chrome interprets it (as commonly used by
mathematicians) as "number of times to repeat".

[Shaun]

Thanks! Just one little bug: The number of iterations needs to be increased by 1 do get the correct duration.

Unfortunately the word "iterations" is ambiguous. Netscape, Firefox, and ImageMagick interpret it (as commonly used
by computer programmers) to mean "number of times to play" while Chrome interprets it (as commonly used by
mathematicians) as "number of times to repeat".

Very interesting information, thank you. IE behaves like Chrome in this case.