extract_frames_from_animated_gif (Source) 

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#!/bin/bash
# extract_frames_from_animated_gif: Extracts frames from an animated GIF :)
# This program writes each extracted frame to its own file in /tmp, then creates
# simple HTML file that shows each individual frame.
# BUUS: This script is part of Brian's Useful Utilities Set


function die {
    echo "extract_frames_from_animated_gif: $1" >&2
    exit 1
}

# Some preliminary checks
[ -z "$1" ] && die "require the name of an image file"
[ -f "$1" ] || die "$1: not found"
[ -r "$1" ] || die "$1: can't read"

# Does the file contain an image?
file "$1" | grep -q image || die "$1: file does not contain an image"

# Determine how many frames there are in the GIF
SCENES=$(identify -format %n $1)
[ $SCENES -lt 2 ] && die "$1: contains only one image"

# Get the basename for the extracted images
X="$(basename "$1" | tr '[A-Z]' '[a-z]')"
BASENAME="${X%.gif}"
[ "$X" = "$BASENAME" ] && BASENAME="${X%.png}"

# Extract the images
rm -f /tmp/*.frame.gif >/dev/null 2>&1
NUMBER_WIDTH=${#SCENES}
convert "$1[0-$SCENES]"  /tmp/${BASENAME}_%0${NUMBER_WIDTH}d.frame.gif

# Build an HTML file with the image sequences
WIDTH=$(identify -format "%w\n" "$1"|head -n 1)
WIDTH=$((WIDTH+4))
COLUMNS=$((1000/$WIDTH))

HTML_FN="/tmp/$BASENAME.html"
cat - <<EOF1 >"$HTML_FN"
<html>
<head>
    <title>$1 - $SCENES frames</title>
</head>

<body>
    <h1>$1</h1>
    <table border="1" cellspacing="0" cell[adding="1">
EOF1

FRAME_NUM=0
ROW_NUM=0
COL_NUM=$((COLUMNS+1))

for FRAME_FN in /tmp/*.frame.gif
do
    if [ $COL_NUM -ge $COLUMNS ]
    then
        [ $ROW_NUM -gt 0 ] && echo -e "\t</tr>" >>"$HTML_FN"
        ROW_NUM=$((ROW_NUM+1))
        COL_NUM=0
        echo -e "\t<tr>" >>"$HTML_FN"
    fi
    FRAME_NUM=$((FRAME_NUM+1))
    COL_NUM=$((COL_NUM+1))
    echo -e "\t\t<td><img src='$FRAME_FN' title='frame $FRAME_NUM' alt='frame $FRAME_NUM' />" >>$HTML_FN
done

# Close off the last row
if [ $COL_NUM -lt $COLUMNS ]
then
    echo -e "\t\t<td colspan='$((COLUMNS-$COL_NUM))' align='center'>End</td>" >>$HTML_FN
fi

# Close off the file
cat - <<EOF2 >>$HTML_FN
    </tr>
    </table>
</body>
EOF2

echo "Wrote $SCENES frames to $HTML_FN"

# vim: tabstop=4