Simple but effective JPG image recovery tool written in c: jpeg-recover2
19. June 2011
This is a c implementation of the jpeg-recover from Adam Glass written in perl.
Though I was happy to see quite a lot images restored from my camera’s memory card using the original tool, it was way to slow for the 4gb it had to process. So this program was written and extended in some ways so it would match more pictures at a fraction of that time.
Please consider that this was written 2-3 years ago. I do not guarantee for success or any possible damage taken through this software. Contact me in case anything went wrong.
How does it work?
Most filesystems such as FAT used on SD cards and other portable memory write a continuos file to the device. This enables us to search for typical jpeg headers to match the beginning and some other pattern to find the end of that photo. So its possible of course, that you won’t find any image if the headers of your camera are not known to that program.
How to use it?
You can compile it on your own from source or download the binary for 32bit (take this one if unsure) or 64bit.
wget http://gimi.name/snippets/uploads/jpeg-recover2.c gcc -o jpeg-recover -s -O3 jpeg-recover2.c
Now you can use it to scan an image made from the device or the device itself. Don’t worry, it won’t be modified.
gimi@meerkat8471:.../jpeg-recover$ ./jpeg-recover -h
Usage: ./jpeg-recover [parameter] disk-image
Parameter:
-o p prepend given p to every written image, defaults to RIMG_
-s b skip b bytes before searching
-a save all matching JPEG header and endings
(!) requires much space and manual selection
default is to save first matching
-l b match images greater than b bytes, defaults to 102400
-u b match images smaller than b bytes, defaults to 5120000
-v be verbose
-h display this help
Example:
./jpeg-recover64 -o out/RIMG_ -s 10000000 /tmp/defect.dd
For more info, please visit: http://gimi.name/go/qiwRE
gimi@meerkat8471:.../jpeg-recover$ ./jpeg-recover /dev/sda1urlencode and urldecode for bash scripting using sed
19. June 2011
To urlencode or -decode strings in bash scripts, one can use simple sed scripts containing one rule for every character. You can download the urlencode.sed and urldecode.sed files.
url="http://gimi.name/snippets/urlencode-and-urldecode-for-bash-scripting-using-sed?randomOption=foo,bar,baz" encodedUrl=$(echo "$url" | sed -f urlencode.sed) url=$(echo "$encodedUrl" | sed -f urldecode.sed) echo "encoded: $encodedUrl" echo "decoded: $url"
Result:
encoded: http%3a%2f%2fgimi%2ename%2fsnippets%2furlencode%2dand%2durldecode%2dfor%2dbash%2dscripting%2dusing%2dsed%3frandomOption=foo%2cbar%2cbaz decoded: http://gimi.name/snippets/urlencode-and-urldecode-for-bash-scripting-using-sed?randomOption=foo,bar,baz
Wget download and index script
2. January 2011
Sometimes there is the need for local copies of websites one found interesting or one has to work with later. This script downloads a single page including pictures and style of a website using wget. For convenience there is an index generated which contains links to all fetched pages in the same directory as well as some detailed information.
Example usage: wget-page http://gimi.name/snippets/
#!/bin/bash DATEFORMAT='%Y-%m-%d %H:%M' while [ -n "$1" ]; do # download page wget --timestamping --page-requisites --convert-links --wait=0 "$1" # add to index echo "$1" >> .index shift done # sort index cat .index | sort | uniq > .index-new mv -f .index-new .index # regenerate index.html ( echo "<html>" echo " <head>" echo " <title>WGET-Page Index</title>" echo " </head>" echo " <body>" echo " <h1>WGET-Page Index</h1>" echo " <ul>" cat .index | while read line; do local=$(echo "$line" | sed -e 's,http://,./,') if [ -e "$local" ]; then link=$(echo "$local" | sed -e 's,\?,%3F,') stamp=$(date +"$DATEFORMAT" -r "$local") # credit for next line goes to http://stackoverflow.com/questions/3833088/extract-title-of-a-html-file-using-grep/3835508#3835508 title=$(awk -vRS="</title>" '/<title>/{gsub(/.*<title>|\n+/,"");print;exit}' "$local") echo " <li>" if [ -n "$title" ]; then echo " <b>$title</b><br />" fi echo " $line<br />" echo " go to <a href='$link'>local copy</a> or <a href='$line'>original page</a><br />" echo " last modified $stamp</li><br />" else echo "$0: Page '$line' not found" 1>&2 fi done echo " </ul>" echo " <hr />" echo " <i>generated by $(basename "$0"), last modification $(date +"$DATEFORMAT")</i>" echo " </body>" echo "</html>" ) > index.html
Extract ogg audio from any clip like flv, mp4, mov, wmv
4. September 2010
I like to download youtube videos using youtube-dl. Sometimes an audio file of that clip would be cool. This can by done with 2ogg movie_file.mp4 "artist name" "song name"
#!/bin/bash # 2ogg: Takes given video to play with mplayer and encode audio to an ogg file. # Consider the loss of quality. if [[ $# -ne 1 && $# -ne 3 ]]; then echo "Usage: $0 <video> [<artist> <title>]" exit fi temp=$(tempfile) mplayer -quiet -ao pcm:fast:file="$temp" -vc dummy -vo null "$1" && oggenc -a "$2" -t "$3" -c "source=$1" -q 7 -o "$1.ogg" "$temp" rm "$temp"
Monitor directory transfer rates e.g. while copying
31. August 2010
This script, let’s call it dirmon, monitors a directory and outputs current change (transfer) rate per second and total disk usage.
It could look like:
gimi@t8417:~$ dirmon /tmp/ 14Byte/s, 211 KBytes total
The code:
#!/bin/bash # notice: this approach assumes 'du' being very quick # if it's not, rates will appear higher function getSize() { du -bs "${1:-.}" 2> /dev/null | cut -f 1 } function abs() { if [ ${1?'error: abs: argument missing'} -lt 0 ]; then echo $(($1*-1)) else echo $1 fi } function bestUnit() { size=${1?'error: bestUnit: argument missing'} for unit in "" K M G; do if [ $(abs $size) -lt 1024 ]; then echo "$size $unit" return fi let size=$size/1024 done echo "$size P" } dir="${1:-.}" echo -ne "sweeping bytes ...\r" lastSize=$(getSize "$dir") while true; do sleep 1 newSize=$(getSize "$dir") let actualDiff=$newSize-$lastSize echo -ne "$(bestUnit $actualDiff)Byte/s, $(bestUnit $newSize)Bytes total \r" lastSize=$newSize done