Transcription Settings

For high quality voice recordings of your Skype conversation, please use the following settings

  • Recording Mode: Stereo – 2 channels
  • Sampling Rate: 16000 Hz
  • Bit Rate: 128 kbps

The first three can be configured from the ‘Recording’ tab of the configuration dialog. The last two are in the ‘Advanced’ Tab.

Tips:

  • First and foremost, use a headset instead of the inbuilt speaker and mic. It helps to keep the background noise to the minimum and reduces the possibility of any echo during the call.
  • If you get an echo then drop the call and try again. If possible, record a test call first and play it back to make sure things are fine.
  • For SkypeOut and Conference calls, ensure that the call quality is good enough before you start the recording. Make a few test calls before the actual one if possible.
  • Close all other applications which might use your internet bandwidth during that period. Usual browsing should not interfere but downloads or uploads (or BitTorrent) severely hampers the call quality.
  • If possible, reboot your machine once before you start on the call. It clears up the memory and performs better.
  • Finally, keep an eye on the status displayed at the bottom of the Toolbar as well during the call. It should be showing ‘Recording in progress’. If not restart the call and the recording.

Explanation:

Technically speaking, these settings are optimal for our system. The Speech Recognition engine that we use works in the wideband mode (16 kHz) and the 128 kbps bit rate preserves the optimal voice quality in the mp3 files. Encoding in two track mode enables us to split up each of the track separately and process them.

If you have more questions then feel free to leave a comment or contact us.

33 Comments

  • Waylon says:

    Good info! The new feature in version 1.0.6.5 is very useful too. One question – is 16000 Hz the maximum sampling rate for all Skype calls? Recently I made a call and it sounded higher quality. Is that possible?

  • Rajiv Poddar says:

    16 kHz is the internal sampling rate of Skype, but we can upsample or downsample while encoding. The quality however depends entirely on Skype. We cannot improve on what is being received from Skype!

  • Paul van der Beek says:

    On my Dell Latitude D620 the other party is not recorded when I have Headphones pluged in. (In skype everyting works normal)
    If I don’t use HeadPhones I get a massive echo.
    Is there a setting which enables me to use my Headset and still record the other party with CallGraph?

  • Rajiv Poddar says:

    @paul, can you pls. run the interactive demo and send me the log file as well as the recorded file. thanks.

  • Xantos says:

    Is it the higher I put up the Sampling Rate, Bit Rate and Encoding Buffer Size the better quality I’ll get? Or is there a particular point that gets the best quality?
    Is there any reason not to put them all on the highest number possible?

    Thanks.

  • Rajiv says:

    @xantos for voice 16KHz sampling rate and 64 kbps is adequate to preserve the quality of it. higher settings wont have much effect on quality.

  • Xantos says:

    Ok thanks a lot Rajiv. Just one more thing – is there a difference in quality or anything at all between WAV and MP3 recording?

  • Rajiv says:

    wav is an uncompressed format, so the original quality is preserved, but files are of large sizes.

  • Tarjei says:

    Hi!
    if I have understood this correctly the programme uses a voice recognition engine to transcribe automatically. What is the accuracy rate, and can you transcribe any language (for instance Norwegian), or only English?
    Also, how long would I have to wait for the transcription after submitting the recording for transcription?

  • Xantos says:

    Tarjei,
    The program is first simply records your call, and saves the audio, then you have the option to submit the audio to be transcribed for a small fee.
    Just clearing that little thing up. I’m not sure of the details – such as whether it transcribes automatically and if they do Norwegian. Someone will probably answer that question for you soon 🙂
    Good luck,
    Xantos

  • Tarjei says:

    Yes thanks Xantos, what I meant was to say that the *company* transcribes after I have made a call recording 🙂

  • Rajiv Poddar says:

    The program does not use Speech Recognition. It simply records and if you want, uploads it to your account. During transcription we internally use an ASR system to reduce the human effort involved.

  • Tarjei says:

    Hi Rajiv
    Yes I understand, but does that mean then that the transcription I receive will be 100% accurate? And I assume that you only transcribe English?
    Also: 50 cents per minute: does that mean 50 cents per minute of the recording, or 50 cents per minute it takes to transcribe the recording?

  • Rajiv Poddar says:

    Accuracy is around 99%. The words that cannot be transcribed are timestamped and marked.

    Its 50 cents per minute of the recorded audio.

  • Tarjei says:

    Great, thanks Rajiv.

  • Lasse says:

    I have awful echo all the time. Skype says that my mic is very low. Yet, the playback has no echo. But during the call, recording, the echo is and does not vanish.

    Withou Call Graph, there is no echo.

  • Lasse says:

    Rajiv,
    Thank you. The cancelling echo helped.

    “Enable Echo Cancellation (Help)
    Far End EC
    Near End EC ”

    Lasse

  • Gabi says:

    I need to record a conversation in skype realized from the computer to a fixed telephone but when I do it I do not listen to the voice of the person who speaks in the fixed telephone. Do you know how I can solve it?

  • Alex says:

    I have the same problem as Gabi. And I think it happened after downloading the last updates for Call Graph.

  • Rajiv Poddar says:

    try turning off Near End EC option from configuration -> advanced tab.

    http://crims.callgraph.in/blog/2009/05/known-issues-v1211/

  • Gurdas says:

    Rajiv,

    I am a new user of CallGraph (ver 1.3.0.0 Beta) ; have tried it with Skype Echo Test Service and it worked very well. Yet to test it with a live call.

    Some questions:

    1. In a reply above you said 64 kbps is good enough, while the software defaults to 128kbps when I hit the ‘Transcription Settings’ button in the ‘Recording’ tab. Why? Should I stick to 128kbps or move to 64kbps if there is minimal loss (I believe my files sizes will be dramatically less in 64kbps vs 128 kbps)?

    2. My ‘Advanced’ tab does not show any setting for Echo. Is that because this is now inbuilt and not user customizable?

    3. What do you recommend for the ‘Enable logging’ option in the ‘General’ tab?

    Thanks!
    Gurdas

  • Rajiv says:

    You can try out various bitrates and choose the one which gives you the best quality.

    The Echo options have been removed in v1.3.0.0.

    Logging helps us locate a problem if you encounter any problems with Call Graph.

  • DM says:

    Hi I am trying to use Call Graph but can’t seem to get started. How do I test if everything is working? Do I have to make a call to somebody else or is there another way to test. At the moment if I hit test on teh pop up toolbar I get an error message: failed to launch Call Graph Browser.
    Thanks

  • Rajiv says:

    You can make a call to echo123 (Skype’s test call service). Please authorize CallGraph to connect to Skype.

  • Amy says:

    I’m using a Voip dual phone and am trying to record calls. Although I am able to make an echo123 test call from the Voip phone, I am not able to record it with Call Graph. I also have tried a SkypeOut call, with no luck. Is there something I need to change to make this work?

  • Rajiv says:

    Please first try with the Skype desktop client and check if it works

  • andre says:

    Call graph recorded me, but the person that I called was not recorded.
    This was a skype-to-cell phone call, not skype-to-skype.

  • Rajiv says:

    Have you authorized CallGraph to connect to Skype? If you have then try recording in mono mode.

  • Julia says:

    Hi, I have a problem.

    I recorded a very important Skype call in stereo mode and as I already inderstood, I should have been set the mode to Mono (grrrr)

    When I playback my mp3 file – I can hear only my voice and dont hear my callee. Can I somehow make it possile to hear the second track – where my callee’s voice actually recorded?

    Maybe some software/players?

    Pl, help!

    Thanks,
    Julia.

  • Rajiv says:

    Please open the file with Audacity and you’ll be able to see the tracks in the file. If your callee’s voice was recorded it will show up there. You can also convert the file to mono with Audacity.

  • Shawn says:

    Usually your program works well for me. Well tonight, everything seemed ok, but when I ended the call it didn’t give me the recording finished reply like it normally does when I end the call on skype. Long story short I only ended up with four minutes of an hour and a half long conversation. Now, the call graph browser says its an hour and a half, but when I open it up its only four minutes worth of audio. I had folks clear across the world staying up late at night to do this and such a let down that I lost all of that audio. Needless to say, I will be looking for a new skype recorder so I don’t have to face this again. I feel like I really let those folks down.

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