[SOLVED] Using ffprobe - getting specific information for use in a script

GPGAgent · 09-06-2019, 09:54 AM

I would like to extract the video bitrate from a command and use that result in a script

ffprobe gives me the infomation:

Code:

charlie@charlie-machine:/media/charlie/TEST$ ffprobe piano.avi 
ffprobe version 1.2.6 Copyright (c) 2007-2014 the FFmpeg developers
  built on May  2 2019 18:57:27 with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04)
  configuration: --enable-libx264 --enable-gpl
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
Input #0, avi, from 'piano.avi':
  Metadata:
    encoder         : Lavf51.12.1
  Duration: 00:56:04.06, start: 0.000000, bitrate: 1443 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (xvid / 0x64697678), yuv420p, 456x304 [SAR 1:1 DAR 3:2], 29.97 tbr, 29.97 tbn, 29.97 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16p, 128 kb/s
charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$

So how can I create a script so that I can use it like this:

Code:

charlie@charlie-machine:/media/charlie/TEST$ VBR.sh piano.avi
1443
charlie@charlie-machine:/media/charlie/TEST$

Cheers folks

rtmistler · 09-06-2019, 10:00 AM

Consider morphing the answer provided here to at least get the line, then the bitrate: term, then just the actual number. I think it'll take a few iterations. Sorry, not an awk expert, but this seems typical of how to approach this:

https://unix.stackexchange.com/quest...t-has-the-text

Or web search with the string "use bash script to search paragraph for a term"

Firerat · 09-06-2019, 10:28 AM

do you want the overall bitrate?
i.e. the Video + the auido?

probably the simplest way

Code:

#!/bin/bash
input="$1"
Bitrate="$(ffprobe -hide_banner "${input}" 2>&1 | grep -o bitrate.*[0-9] )" 
echo "${Bitrate}"
echo "${Bitrate#bitrate: }"
Bitrate="${Bitrate#bitrate: }"
echo "${Bitrate}"

# 
# The 2>&1  is redirecting stderr to stdout
# then you can use grep
# -o, --only-matching
#      show only nonempty parts of lines that match
#

Firerat · 09-06-2019, 10:35 AM

now , there is another way

Code:

ffprobe -hide_banner -print_format json -show_format "${input}"

this will spit out json

you could go parsing that with grep/sed/awk

but jq is much easier

Code:

#!/bin/bash
input="$1"
Bitrate(){
ffprobe -hide_banner \
   -print_format json \
   -show_format "${input}" 2>/dev/null \
   | jq -r ".format.bit_rate"
}
Bitrate

Note , the bitrate in that is bits and not kb !!

Firerat · 09-06-2019, 10:40 AM

another??

mediainfo

Code:

mediainfo --Output="General;%OverallBitRate%" "${input}"

you can get a massive list

Code:

mediainfo --Info-Parameters

HappyTux · 09-06-2019, 11:09 AM

Quote:

Originally Posted by GPGAgent

I would like to extract the video bitrate from a command and use that result in a script

ffprobe gives me the infomation:

Code:

charlie@charlie-machine:/media/charlie/TEST$ ffprobe piano.avi 
ffprobe version 1.2.6 Copyright (c) 2007-2014 the FFmpeg developers
  built on May  2 2019 18:57:27 with gcc 7 (Ubuntu 7.3.0-27ubuntu1~18.04)
  configuration: --enable-libx264 --enable-gpl
  libavutil      52. 18.100 / 52. 18.100
  libavcodec     54. 92.100 / 54. 92.100
  libavformat    54. 63.104 / 54. 63.104
  libavdevice    54.  3.103 / 54.  3.103
  libavfilter     3. 42.103 /  3. 42.103
  libswscale      2.  2.100 /  2.  2.100
  libswresample   0. 17.102 /  0. 17.102
  libpostproc    52.  2.100 / 52.  2.100
Input #0, avi, from 'piano.avi':
  Metadata:
    encoder         : Lavf51.12.1
  Duration: 00:56:04.06, start: 0.000000, bitrate: 1443 kb/s
    Stream #0:0: Video: mpeg4 (Simple Profile) (xvid / 0x64697678), yuv420p, 456x304 [SAR 1:1 DAR 3:2], 29.97 tbr, 29.97 tbn, 29.97 tbc
    Stream #0:1: Audio: mp3 (U[0][0][0] / 0x0055), 44100 Hz, stereo, s16p, 128 kb/s
charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$

So how can I create a script so that I can use it like this:

Code:

charlie@charlie-machine:/media/charlie/TEST$ VBR.sh piano.avi
1443
charlie@charlie-machine:/media/charlie/TEST$

Cheers folks

Code:

#!/bin/bash
ffprobe $i &> temp.txt; cat temp.txt | grep bitrate | cut -d ":" -f 6 ; rm temp.txt

The result of the command run on a file locally.

Code:

MacUser2525:~$ ffprobe /Volumes/Sea_To_Do/watching/TV/Department_S_Series_01/Department_S-S01xE05-One_Of_Our_Aircraft_Is_Empty.mkv &> temp.txt; cat temp.txt | grep bitrate | cut -d ":" -f 6
 1105 kb/s

Or if wanting to use mediainfo as suggested in previous post, the script I have for getting my information on multiple files. I adapted the line above from one of them in it.

Code:

MacUser2525:~$ cat Bin/mediainfo_video_audio.sh 
#!/bin/bash

# Get directory script is running in
DIR="$(dirname "$PWD")/$(basename "$PWD")"

# Change to directory
cd $DIR

# Now process all .mkv files under that directory
for i in $(find $PWD -not -path '*/\.*' | sort  | grep .mkv ); do

	# Use mediainfo to get information needed
	/usr/local/bin/mediainfo "$i" &> /tmp/tmpinfo

	# Get channels in mediainfo created file used for audio mono/stereo/surround
	Title=$(cat /tmp/tmpinfo | grep -C 2 Duration | grep "Channel(s)" | cut -d ":" -f 2 | cut -d " " -f 2)
	
	# File processing according to channels found
	case $Title in
	
		1) 
			Title=Mono
		;;
		
		2)
			Title=Stereo
		;;
		
		6)
			Title=Surround
		;;
	esac
		
	# Get video width in mediainfo created file
	Width=$(grep Width /tmp/tmpinfo)
	
	# Get video height in mediainfo created file
	Height=$(grep Height /tmp/tmpinfo)
	
	# Get bit rate in mediainfo created file
	Bitrate=$(grep "Overall bit rate" /tmp/tmpinfo)
	
	# Get aspect ratio in mediainfo created file
	Aspect=$(grep "Display aspect ratio" /tmp/tmpinfo)
	
	# Get video codec in mediainfo created file
	Video=$(cat /tmp/tmpinfo | grep -C 3 Width | grep "Codec ID" | cut -d ":" -f 2)
	
	# Get audio codec in mediainfo created file
	Audio=$(cat /tmp/tmpinfo | grep -C 3 "Channel(s)" | grep "Codec ID" | cut -d ":" -f 2)
	
	# Get file size in mediainfo created file
	Size=$(grep "File size" /tmp/tmpinfo)

	# Get audio channels in mediainfo created file positions
	Channel=$(grep "Channel(s)" /tmp/tmpinfo)
	
	# Get audio channels positions in mediainfo created file 
	Channelpos=$(grep "Channel positions" /tmp/tmpinfo)
	
	# Get duration of video in mediainfo created file
	Duration=$(cat /tmp/tmpinfo | grep -C 1 "File size" | grep Duration)

	# Echo what was done
	echo $i
	echo "$Size"
	echo "$Duration"
	echo "$Bitrate"
	echo "Codec ID                                 :""$Video"
	echo "$Width"
	echo "$Height"
	echo "$Aspect"
	echo "Codec ID                                 :""$Audio"
	#echo "Audio                                    :" "$Title"
	echo "$Channel"
	echo "$Channelpos"
	echo " "

	# Remove temporary file created with mediainfo
	rm /tmp/tmpinfo

# Done processing all files
done

Firerat · 09-06-2019, 11:28 AM

I don't get it

why would you

Code:

cat temp.txt | grep bitrate

?

why not

Code:

grep bitrate temp.txt

hell, why even have the temp.txt

Code:

ffprobe $i 2>&1 | grep bitrate | cut -d ":" -f 6

regards mediainfo and writing to a temp file

Code:

tempVar="$(mediaino --Output=JSON "$inputfile")"

you can then query that later with jq ( or your pipe trains )

Code:

<<<$tempVar jq .

Edit:
I'll throw this in aswell
mediainfo uses @ in some of its lables
I havn't figured out how to escape those with jq.. so

Code:

<<<${tempVar//@} jq .

which simply deletes all the @

ondoho · 09-06-2019, 11:48 AM

Did nobody consider that ffprobe might be able to do it all by itself?
https://video.stackexchange.com/a/16359

Firerat · 09-06-2019, 11:53 AM

Quote:

Originally Posted by ondoho

Did nobody consider that ffprobe might be able to do it all by itself?
https://video.stackexchange.com/a/16359

I just like json

GPGAgent · 09-06-2019, 12:33 PM

Quote:

Originally Posted by ondoho

Did nobody consider that ffprobe might be able to do it all by itself?
https://video.stackexchange.com/a/16359

Good, but my avi file returns a bitrate=N/A

Code:

charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$ ffprobe -v error -select_streams v:0 -show_entries stream=bit_rate -of default=noprint_wrappers=1 piano.avi 
bit_rate=N/A

GPGAgent · 09-06-2019, 12:40 PM

Quote:

Originally Posted by Firerat

another??

mediainfo

Code:

mediainfo --Output="General;%OverallBitRate%" "${input}"

you can get a massive list

Code:

mediainfo --Info-Parameters

Cheers Firerat, this will do the job:

Code:

charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$ bitrate=$(( $(mediainfo --Output="General;%OverallBitRate%" piano.avi) / 1000 ))
charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$ echo $bitrate 
1443

So I'll add the above to my script and I have the bitrate to use in further processing - nice.

Thanks to everyone else that replied. All good stuff

Firerat · 09-06-2019, 02:04 PM

np

I used to use mediainfo a lot, not so much now.

mind if I ask what you are using the ABR for?

RE-Encoding ?
Personally I would use crf ( constant rate factor )
but maybe use the ABR to cap it ( so I defiantly don't get a larger file )

copy audio ( I would probably go with opus if size was a concern )
video as hevc

Code:

input="piano.avi"
output="piano.mkv"
br="$(( that long commnd ;)  ))"
ffmpeg -i "${input}" \
    -c:a copy \
    -c:v libx265 \
    -preset medium \
    -x265-params vbv-bufsize=${br}:vbv-maxrate=${br}:crf=24 \
  "${output}"

in bold, since the rate is capped at the same as the source ( well not quite *) I should not get a file larger

* we only capped the video bitrate , we got vid+audio bit rate

so it might end up slightly larger

I don't understand all the in and outs of ffmpeg encoding
I've read many a flame war where two or three ppl argue over this and that param.

What I have found is
preset , the faster it is the worse the quality and the *smaller* the file size

crf, the lower it is the better the quality, and the file is larger.

x265 ( hevc ) defaults are medium preset and crf of 28

if the source is bad quality / low resolution, I find a lower crf gets a better end result
Higher quality source , high res.. you can get away with a higher crf

ondoho · 09-07-2019, 01:20 AM

Quote:

Originally Posted by GPGAgent

Good, but my avi file returns a bitrate=N/A

Code:

charlie@charlie-machine:/media/charlie/IOMEGA_01/USENET/DVD2/TEST$ ffprobe -v error -select_streams v:0 -show_entries stream=bit_rate -of default=noprint_wrappers=1 piano.avi 
bit_rate=N/A

try to remove "-select_streams v:0" from that command.
Also, while troubleshooting, remove "-v error".

GPGAgent · 09-08-2019, 05:31 PM

Quote:

Originally Posted by Firerat

np

I used to use mediainfo a lot, not so much now.

mind if I ask what you are using the ABR for?

RE-Encoding ?
Personally I would use crf ( constant rate factor )
but maybe use the ABR to cap it ( so I defiantly don't get a larger file )

copy audio ( I would probably go with opus if size was a concern )
video as hevc

Code:

input="piano.avi"
output="piano.mkv"
br="$(( that long commnd ;)  ))"
ffmpeg -i "${input}" \
    -c:a copy \
    -c:v libx265 \
    -preset medium \
    -x265-params vbv-bufsize=${br}:vbv-maxrate=${br}:crf=24 \
  "${output}"

in bold, since the rate is capped at the same as the source ( well not quite *) I should not get a file larger

* we only capped the video bitrate , we got vid+audio bit rate

so it might end up slightly larger

I don't understand all the in and outs of ffmpeg encoding
I've read many a flame war where two or three ppl argue over this and that param.

What I have found is
preset , the faster it is the worse the quality and the *smaller* the file size

crf, the lower it is the better the quality, and the file is larger.

x265 ( hevc ) defaults are medium preset and crf of 28

if the source is bad quality / low resolution, I find a lower crf gets a better end result
Higher quality source , high res.. you can get away with a higher crf

Hi Firerat, Yep I'm re-encoding a load of wmv's, avi's mph's and so on to mp4, and your tips will help loads.

I'm trying to maintain the size and aspect ratio and using a video bitrate of 1000K or if the original is less use that instead. Audio I'm just copying

GPGAgent · 09-08-2019, 05:40 PM

Quote:

Originally Posted by ondoho

try to remove "-select_streams v:0" from that command.
Also, while troubleshooting, remove "-v error".

ondoho, Cheers that worked, almost:

Code:

ffprobe -v error -show_entries stream=bit_rate -of default=noprint_wrappers=1 piano.avi 
bit_rate=N/A
bit_rate=128000

But I get two bit_rate lines, how can I exclude the N/A one, and I guess this is the audio bitrate?