Version 3.1


  Camtasia Studio

The Fundamentals of
  Screen Recording



      By TechSmith Corp.

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Camtasia Studio 3.1                                                  The Fundamentals of Screen Recording




Getting Started: The Fundamentals of Screen Recording                                                          4

     Understanding Bandwidth and Streaming Media Production............................................5
          File Size, Bit Rate, Bandwidth and Data Transmission ...................................................6
          Bandwidth and Streaming Media File Transmission .......................................................7
          Video Compression and Key Frames...............................................................................8
             Key Frames versus Delta Frames ....................................................................................................... 8
             Frame Rate and Bandwidth ................................................................................................................ 8
          Network Congestion, Bandwidth Spikes, and Buffering .................................................9
          Audio and Bandwidth.....................................................................................................10

     Understanding Video and Audio Codecs.............................................................................11
             What is a Codec?.............................................................................................................................. 11
             How do Codecs work? ..................................................................................................................... 11
             Lossless vs. Lossy Codecs................................................................................................................ 11
             Identifying the Codecs that are Installed on your System ................................................................ 12
             Determining the Codec a Video is Compressed With ...................................................................... 12
          About the TechSmith Screen Capture Codec (TSCC) ...................................................13
          About the Microsoft Video 1 Codec ..............................................................................14
          Audio Codecs Overview ................................................................................................16
          The Best Overall Codec Options While Recording .......................................................18

     Getting Great Sound in your Recordings ............................................................................19
          Barely Audible Recordings ............................................................................................20
          Monitoring your Audio Level as You Record ...............................................................21
          Solving Common Sound Problems ................................................................................22
          Recording Audio from Other Applications ....................................................................24
          Looking at Several Different Kinds of Microphones.....................................................25
          Tips for Recording Audio in Various Scenarios ............................................................27

     Learning about the File Size .................................................................................................28
          Video Dimensions ..........................................................................................................31

Video Production & File Formats                                                                    34

     Produce your Video ...............................................................................................................35
          Share your Video............................................................................................................36



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     Help Me Choose a File Format .............................................................................................37
         Audio Video Interleave (AVI) and CD-ROM Distribution ...........................................39
         Audio Video Interleave (AVI) & DVD Productions .....................................................40
         Macromedia Flash (SWF/FLV) .....................................................................................41
         QuickTime (MOV).........................................................................................................42
         Windows Media (WMV - Streaming Format) ...............................................................43
            Recommended Settings for Normal Screen Recordings .................................................................. 43
            Recommended Settings: Higher Motion Screen Recordings & Camcorder Videos ........................ 44
         RealMedia Streaming Media (RM)................................................................................45
         Camtasia for RealPlayer (RealPlayer Plug-In(CAMV)) ................................................46
         GIF Animation File (GIF) ..............................................................................................47

     Looking at the Different Media Players...............................................................................48
         Comparing Media Players ..............................................................................................49
         About Camtasia Player...................................................................................................50
         Making Camtasia Player your Default Player................................................................52
         Camtasia Player & Pack and Show ................................................................................53
         Looking at Common Media Player Problems ................................................................54

Tips, Tricks, & Best Practices                                                       56

     Preventing Blurry Videos......................................................................................................57

     Preventing Blank (Black) Videos..........................................................................................58

     Using the Hotkeys and Keyboard Shortcuts .......................................................................60
         Camtasia Studio's Main Interface...................................................................................61
         Camtasia Audio Editor ...................................................................................................62
         Camtasia MenuMaker ....................................................................................................63
         Camtasia Player..............................................................................................................64
         Camtasia Theater............................................................................................................65

     Tips for Scripting and Audio ................................................................................................66

     Before you Record Worksheets ............................................................................................67
         Screen Resolution Checklist...........................................................................................68
         Video Quality and File Size Checklist ...........................................................................69
         Video Compression Checklist........................................................................................70


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          Video Type & Playback Checklist .................................................................................71
          Audio Compression Checklist........................................................................................74

     Contact TechSmith Technical Support................................................................................75

Index                                                                76




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Getting Started: The
Fundamentals of Screen
Recording


The information contained within this guide will help you understand the guiding principles behind successful
screen recording.
Before you begin working with Camtasia Studio, we recommend that you read through this guide to become
familiar with some of the terms and concepts that you will come across when making your videos. Please
refer to the Camtasia Studio Help file for a comprehensive explanation of all Camtasia Studio’s features and
options.
You will find the following topics included within the scope of this guide.
Understanding Bandwidth and Streaming Media Production on page 5.
Understanding Video and Audio Codecs on page 11.
Getting Great Sound in your Recordings on page 19.
Learning about the File Size on page 28.
Produce your Video on page 35.
Help Me Choose a File Format on page 37.
Looking at the Different Media Players on page 48.
Tips, Tricks, & Best Practices on page 56.
Preventing Blurry Videos on page 57.
Preventing Blank (Black) Videos on page 58.
Using the Hotkeys and Keyboard Shortcuts on page 60.
Tips for Scripting and Audio on page 66.
Before you Record Worksheets on page 67.




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Understanding Bandwidth and Streaming Media
Production
Bandwidth is simply a measure of the amount of data that can be transmitted through a connection over a
given amount of time. Bandwidth, also called data transfer rate, is usually expressed in bits per second (bps).
Bandwidth is synonymous with capacity. Every machine on the Internet is connected by a cable or another
type of connection. This cable has a capacity; it can carry a certain amount of information through it, similar
to a hose. This cable may have a high or low capacity. If you compare a garden hose to a fire hose, more
water can pass through the fire hose in a minute than a garden
hose.
The slowest of these capacities is the bandwidth of the line; it’s
the fastest you can communicate between the ends. Think of the
cable as a long tube with someone pouring water into it on one
end, and someone draining it out the other. You cannot take out
more than was put in, and if you pour it in too fast the water will
spill (losing data).
For example, a 28.8 kbps dialup modem connection is much
slower than a cable modem connection. The cable modem
connection can download more data than the 28.8 kbps dialup
modem connection can over the same period of time. The cable
modem has a higher bandwidth connection than the 28.8 kbps
dialup connection does. High bandwidth allows fast transmission
of data or high volume transmission just like the fire hose.


Continue with the following topics:
File Size, Bit Rate, Bandwidth and Data Transmission on page 6.
Bandwidth and Streaming Media File Transmission on page 7.
Video Compression and Key Frames on page 8.
Network Congestion, Bandwidth Spikes, and Buffering on page 9.
Audio and Bandwidth on page 10.




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File Size, Bit Rate, Bandwidth and Data Transmission
This section describes the measurements used for file size and bandwidth and describes how these
measurements relate to data transmission.


File Size
File size is measured in bytes. One kilobyte (K or KB) equals about 1,000 bytes. For example, a small image
file might be 20K or about 20,000 bytes in size.
To learn more about file size, continue with Learning about the File Size on page 28.


Measurements and Conversions
The following chart describes the units, measurements, and conversions for data transmission.
    Usage          Measurement        Equivalence (Abbreviation)
                 (Abbreviation)
File Size        1 kilobyte (K or KB)      1000 bytes
Conversion       1 byte             8 bits
Bit Rate        1000 bits per second (bps)   1 kilobit per second (kbps)
(Bandwidth)


Data Transmission
Data transmission measured in bits per second (bps) is called the baud rate or bit rate—it is the measure of
bandwidth. If a computer can receive 5KB (5,000 bytes) in a second, it would take 4 seconds for it to receive
a file 20K in length.
But bandwidth is not measured in bytes—it is measured in bits. 1 byte contains 8 bits. So, if a computer can
receive 5K (5,000 bytes) in one second, it can receive 40,000 bits per second. 5,000 bytes x 8 bits = 40,000
bits per second or 40 kbps.
Data transmission measured in bits per second is called the baud rate or bit rate and is the measure of
bandwidth. It is commonly measured in thousands of bits per second or kilobits per second. The abbreviation
for kilobits per second is kbps or simply k. One kilobit equals about 1,000 bits.
If a computer connects to the Internet using a 56 kbps dialup modem, in theory, it means that the computer
could receive 56,000 bits per second (56 kbps). That would mean that the computer could receive about 7,000
bytes per second. Remember that a byte equals 8 bits, so 56,000 bps/ 8 bits = 7,000 bytes.
So, to receive the 20K image file, the 56 kbps dialup connection would require slightly less than 3 seconds to
receive the file (20K/7,000 bytes=2.85 seconds).
Data transmission measured in bits per second is the bandwidth of the connection. In this case the bandwidth
is 56 kbps.

Note:    A 56 kbps modem cannot actually communicate at 56 kbps. In reality it’s more like 35-45 kbps. A
      56 kbps modem connection generally only provides 35-45 kbps of bandwidth.


Continue with Bandwidth and Streaming Media File Transmission on page 7.




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Bandwidth and Streaming Media File Transmission
Computer video files are basically a number of still images called frames that are combined sequentially into
one file. When the file is played on a player such as Windows Media Player, it goes through the video file and
displays each frame sequentially in quick succession to create the illusion of motion similar to a video film
rolling through a movie projector.
When a file is streamed, frames are continuously delivered from the computer that is streaming the video to
the computer that is playing it. Each frame is displayed as it is received.




For example, consider a computer connected to the Internet using a dialup modem. If the modem is connected
at 40 kbps, that would mean that it could receive 5,000 bytes (5 KB) of data per second. If each frame of the
video was only 5K then the modem could only receive 1 frame per second.
Commercial motion pictures are 24 fps (frames per second), television is 30 frames per second. The more
                      frames per second (fps), the smother the video playback appears
                      to the viewer. So, a 1 fps video is a very slow and choppy video.
                      The number of frames per second (fps) is also called the frame
                      rate.
                        With a higher bandwidth connection, more frames per second
                        could be received. With a 128 kbps ISDN connection for
                        example, 32 5K frames could be delivered per second.
                        But, a 5K image or frame is not very big. A small 320x200, 16
                        bit JPEG file can easily be 20K in size. So, for the modem
                        connected with only 40 kbps of bandwidth, it would take 4
                        seconds to receive only one frame of the video! At that rate, the
                        video would degrade into a slide show, and not be a video at all.
                        This is the reason why many videos that you see online or on
                        news sites are very small, and why a dialup Internet connection
                        just does not have enough bandwidth to enjoy a very rich
                        multimedia experience.


Continue with Video Compression and Key Frames on page 8.




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Video Compression and Key Frames
As static image files are compressed using various compression algorithms the video and audio data in
streaming media files is compressed. This reduces the number of bytes in each frame thus reducing the
bandwidth requirement to deliver the video. While data compression helps considerably, another step is taken
to reduce bandwidth requirements.
Video files are simply a number of still images called frames that are combined sequentially into one file.
Each frame is displayed at some given number of frames per second (fps) to create the illusion of movement.
But many times there is no movement or change in the video between one frame and the next.
For example, a video demonstration of an application may show the opening of a new window and then not
change for several minutes while the audio narration explains the application. If nothing changes, there is no
reason to send a new frame of video data. The player can just sit there and display the same frame. This
hugely reduces bandwidth requirements.
Consider a video that is a demonstration of an application. Perhaps, all that is changing in the video is that the
cursor moves around the application as the author of the video points out different areas in the application.
Instead of sending the entire frame, only the changes to the new frame are sent. If the only change between
one frame and the next is that the cursor is in a different position, then the only change to the image is
drawing the area where the cursor was to the cursor in its new position. The mouse pointer is very small and
the number of bytes of video data that represents it is minimal, so very little video data needs to be
transmitted to reflect the change between frames. Sending only the part of the frame that has changed can also
greatly reduce bandwidth requirements.
Changes from one frame to the next, increases the bandwidth requirements of the video. The more movement
occurs, the more area of the screen is changed, resulting in larger amounts of video data that must be sent to
update to the next frame. If the entire screen changed from one frame to the next, the entire frame would have
to be sent.

Key Frames versus Delta Frames
There are two types of video frames: key frames and delta frames. Key frames contain all of the pixels that
comprise the complete frame. Delta frames only contain what has changed from the previous frame. Key
frames are placed in the video at regular intervals, either every so many seconds or so many frames. Windows
Media Encoder, for example, defaults to 1 key frame every 10 frames. It looks something like this:
Key frame | delta frame | delta | delta | delta | key | etc…
If there is no change from one frame to the next, delta frames can contain 0 bytes of data. If the only change
from one frame to the next is the movement of the mouse pointer, the delta frame would contain very little
data. If the entire screen had changed, the delta frame would be as large as a key frame, as it would have to
contain bytes of data representing every pixel in the frame. Although high key frame rates increase file size,
they improve seeking.


Frame Rate and Bandwidth
Frame rate may or may not have much effect on the bandwidth requirements of the video. If there is a lot of
change between frames, then the size of each frame is larger and more data must be transmitted for each
frame. In this case, higher capture frame rates require increased bandwidth. But, if there is little or no change
between frames, then little or no video data is transmitted for each frame. So, depending on the content of the
video, increasing the frame rate may have little or great effect on how much bandwidth is required.
Continue with Network Congestion, Bandwidth Spikes, and Buffering on page 9.




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Network Congestion, Bandwidth Spikes, and Buffering
Streamed video is displayed as it is received. With streaming video, the video can start to display the data
before the entire file has been transmitted. If for some reason the data stream is slowed or interrupted, the
video will stop playing. Network congestion and other problems are fairly common, and to help ameliorate
the interruption of the data stream, buffering is implemented.




Buffering works by storing a portion of the video locally, and then playing the video by retrieving data from
the local buffer. Before the video starts playing, the player downloads some amount of the video and stores it
locally. Generally this is not a large portion of the video, usually 10 seconds or so. It then plays the video
from this local buffer while continually downloading more of the video to keep the buffer full.
If the network becomes congested, or if the stream is interrupted for some reason, the player can continue
playing from the buffer, and hopefully the interruption will be corrected before the buffer is depleted and the
video stops playing.
Buffering can also help with encoding videos that contain spikes of high bandwidth. This can occur if
something in the video suddenly requires more bandwidth. For example, in a video demonstrating an
application, the only movement might be the mouse pointer moving across the screen for many frames. If the
                               author of the video clicks a button in the
                               application that causes a new window to open,
                               the entire frame might change, requiring a large
                               block of data needing to be transmitted to
                               update the next frame. This causes a spike in
                               the required bandwidth.
                                Modern media encoders take into account the
                                extra time afforded by the buffer. While the
                                extra data caused by the increase in bandwidth
                                is being delivered, the video can be played from
                                the buffer, thereby not interrupting playback.
                                Increasing the amount of buffering time can
                                make the difference between a failed or a
                                successful encoding process.




Continue with Audio and Bandwidth on page 10.




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Audio and Bandwidth
Audio is a very important factor when considering streaming content and bandwidth. Audio requires
bandwidth just as video does. The higher the quality of the audio, the more bandwidth it will consume.
That is why streaming media encoders such as
Media Encoder always use compressed audio.
Uncompressed audio gobbles up bandwidth.
PCM uncompressed audio, 22.050 kHz, 16 bit
mono for instance requires 43 kbps of
bandwidth. If you consider a dialup modem
connected at 40 kbps, it is evident that any
attempt to stream this is doomed to fail. Highly
compressed, lower quality audio such as
ACELP.net 8 kHz, mono, for example, requires
only 5 kbps of bandwidth.




Continue with the following topics:
Understanding Video and Audio Codecs on page 11.
Audio Codecs Overview on page 16.




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Understanding Video and Audio Codecs

What is a Codec?
The term codec is an abbreviation for compressor/decompressor. A codec is an algorithm that compresses
data when you are recording and producing a movie and decompresses the data when the video is being
viewed. Codecs affect both the image quality and the file size of videos. Certain codecs are better to use than
others in certain situations, because of the way they compress content.


How do Codecs work?
A codec is encoded to a file when a video is recorded. The codec compresses the data to make the bit rate and
file size smaller. This allows for the video to be easily stored and streamed over a network. When the video is
played on a media player, such as Microsoft Windows Media Player, the player decompresses the video file
for playback.
When a video is compressed with any particular codec, that same codec must be installed on the computer
that is going to view the video, because the video must be decompressed with the same codec that it was
compressed with. If the codec is not installed on the computer playing the file, then the media player will try
to download the codec so that it can understand how to decompress the file.
There are two main advantages of using a codec for your video file:
  • Storage space – A compressed file takes up less storage space than an uncompressed file. This also
    allows you to store more files on your computer, add more content onto CD-ROMs, etc.
  • Transfer time – Compressed file sizes are smaller than uncompressed file sizes. With smaller file
    sizes and lower bit rates, video files can be stored and streamed over a network more quickly and
    easily.


Lossless vs. Lossy Codecs
Video codecs can be divided into two categories: lossless and lossy. Lossless codecs maintain perfect image
quality when the video is compressed, while lossy codecs sacrifice image quality for compression. Many
video codecs such as Microsoft Video 1 are lossy codecs, but the TechSmith Screen Capture Codec (TSCC) is
lossless.
If you start out with a video made using either a lossy audio or video codec, each time you reproduce the
video the quality will degrade. It is similar to making a copy of a videotape and then proceeding to make a
copy from that copy. The video quality of each copy is severely degraded, and eventually will become too
difficult to view.
We recommend using the default codec options (TSCC and PCM uncompressed mono audio) to record your
video. Since the TechSmith Screen Capture Codec (TSCC) is lossless, it does not sacrifice image quality for
compression, making TSCC an excellent choice for recording your master video.




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Identifying the Codecs that are Installed on your System
  •  In Windows 2000:
     Select Windows Start > Settings > Control Panel > Hardware > Device Manger > Sound, Video
     and Game Controllers > Video Codecs or Audio Codecs.
  •  In Windows XP:
     Select Windows Start > Control Panel > Sounds, Speech, and Audio Device Properties > Sounds
     and Audio Devices > Hardware tab > Choose Video Codecs or Audio Codecs from the list >
     Properties.


Determining the Codec a Video is Compressed With
Within Windows Explorer, right-click the video file name, and then select Properties > Summary tab >
Advanced.

The codec is listed in the Video Compression entry. You can also right-click on a thumbnail within Camtasia
Studio and select Properties to see both audio and video codec information.


Continue with:
About the TechSmith Screen Capture Codec (TSCC) on page 13.
About the Microsoft Video 1 Codec on page 14.




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About the TechSmith Screen Capture Codec (TSCC)
By default, Camtasia Recorder uses the TechSmith Screen Capture Codec (TSCC) for video compression
during recording. This codec was created by TechSmith specifically for screen recordings of standard
Windows and desktop content. A big advantage to using the TSCC is that is provides lossless compression.
This means that any recordings made with TSCC will always be 100% perfect quality - even through multiple
decompression/recompression cycles that are typical during the production process.
Other advantages to using the TSCC are:
  • It’s built into the Camtasia Player.
  • The ability to playback videos on the host PC without having to install the TSCC. There are no
    charges, royalties, or licensing requirements involved in distributing videos encoded with TSCC or
    with distributing the codec to others for viewing.
  • Lossless preservation of 100% of the image quality, even through multiple
    decompression/recompression cycles that are typical during the production process.
  • Optimization for screen captures so that the resulting files are small and highly compressed.
  • Exceptional compression speed at all color depths.
Overall, TSCC is really designed for content that consists mostly of solid blocks of color such as that found in
most Windows and other desktop PC applications.
The TSCC video codec does not compress well for real-world video, camera video, music videos, video
conference windows, video with high motion, gradients, and dithered images, or any other content that does
not contain a proportionately higher number of areas containing solid blocks of color. In fact, you may find
that if the TSCC is used with one of these kinds of recordings, the final file size of that recording may be
close to that of a totally uncompressed video.
It is very important to only use TSCC to compress the content that it is intended for. The images below
illustrate the type of content that is best for TSCC compression.




Sample #1
In sample number one on the left, you can easily see solid blocks of color within this image. This makes it an
ideal candidate for TSCC compression.
Sample #2
In sample number two on the right, it is easy to see that there are no solid blocks of color within this image.
Therefore, the TSCC codec would not be a good choice for compression.




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About the Microsoft Video 1 Codec
Microsoft Video 1 is a standard video codec that comes with Windows and provides mid-range compression,
with a relatively small amount of quality loss.
The benefits of using the Microsoft Video 1 codec include:
  •  Standard video codec that comes with Windows.
  •  Provides mid-range compression.
  •  Relatively small amount of quality loss (lossy).
  •  Good when real world video, gradients, or dithered images are being recorded.


It is very important to only use the Microsoft Video 1 codec to compress the content that it is intended for.
When creating a ten second video with the following images using both the TSCC and the Microsoft Video 1
codecs, the subsequent results were achieved:


Image #1 Video Sample
Using image number one, the final TSCC compressed video was almost half the size of the same video
compressed using the Microsoft Video 1 codec. This is because the TSCC is designed specifically for the type
of content shown in image one, that is, mostly large, solid blocks of color.


Image #2 Video Sample
On the other hand, when using image number two, the final TSCC compressed video was nearly 60 percent
larger than the video compressed with the Microsoft Video 1 codec. This makes Microsoft Video 1 a good
alternative to TSCC when real-world video, photos, gradients, or dithered images are being recorded.




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Looking at the Lossy Attributes
It is important to note that the Microsoft Video 1 is a lossy codec and does not compress videos nearly as well
as some of the more modern video codecs, such as Microsoft MPEG-4 V2 or, in some situations, TSCC. This
means that some color banding and degradation of antialiased objects can occur.
This quality loss is illustrated in the following two images.




Sample #1
In sample number one on the left, the image was compressed using TSCC. All of the aspects of the original
image are preserved perfectly, including all of the antialiased objects and the color gradients.


Sample #2
In sample number two on the right, the image was compressed using Microsoft Video 1.
Note the blocky distortions around the antialiased objects such as the rune in the title bar and the folder icon.
Also, many of the gradient colors are now noticeably banded.


Continue with Audio Codecs Overview on page 16.




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Audio Codecs Overview
Depending on the audio configuration, the audio portion of your recording file may be 150 or more times
larger than the video portion. For example, a 464x412, 62 second video compressed with TSCC and
containing no audio was 64K. The same video with PCM uncompressed audio, 48 kHz 16 bit stereo was
11.6MB!
In the same way that video files are compressed with various video codecs, audio is compressed using audio
codecs. The choice of an audio codec will not only be a major determining factor in the size of the video, but
also affect the audio quality.

Note:    For voice recordings, stereo is generally not needed and will double the size of the audio portion
      of the file.


Consider the following AVI video file. The only difference is the audio compression used. Note how the file
size varies when the file is compressed with various audio codecs.
                  Audio Setting                   File Size
No Audio                                     300 KB
PCM 22.050kHz, 16 bit, Mono Uncompressed Audio (Camtasia Recorder's       2.7 MB
default settings)
CCITT u-Law 11.25kHz, 8 bit, Mono Compressed Audio                911 KB
Mpeg Layer-3 24.00 kHz, Mono Compressed Audio                  471 KB


To get the best quality audio, use the uncompressed PCM codec in your Camtasia Studio project. Continue
using PCM throughout the entire production and editing process. Then, when your project is finished, make
copies of the original using another audio compressor, if you so desire.


Comparing Audio Codecs
When using audio, keep these tips in mind:
 • MPEG Layer 3 is an excellent audio codec. It produces small files sizes and maintains good audio
   quality. MPEG Layer 3 does have some drawbacks. It may not be installed on all computers. The
   only way to ensure it is installed is to install Media Encoder from Microsoft.
 • Windows Media Player 8 on XP cannot play MPEG Layer 3 encoded AVIs. It thinks that the AVI is a
   MP3 file and only plays the audio. One workaround for this problem is to distribute the Camtasia
   Player with your videos.
 • GCM 6.10 is good for voice compression.




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Audio Codec Tips
Be careful in selecting audio codecs. Some audio codecs produce horrible sounding audio—from scratchy
static noise to sounding like the Tin Man talking into a drain pipe. You will want to select the best codec that
meets your compression and viewing needs.
   • To find the best audio codec for your video, experiment by making a short video using Camtasia
     Recorder's default configuration (PCM uncompressed audio, 16 bit, 20.050kHz). Then in Camtasia
     Studio, try saving your video using various audio codecs at different sample rates.
   • For voice, stereo is generally not necessary and will double the size of the file. If you need higher
     quality audio you can increase the sample rate, but keep in mind that it will dramatically increase the
     file size.
   • Camtasia Studio supports all audio codecs installed on your computer. Be aware that some of the
     audio codecs Camtasia finds and displays cannot be used when producing new videos due to
     licensing restrictions by the owners/authors of the codec. If you try to use one of these restricted
     audio codecs, Camtasia displays a dialog saying that you must choose a different codec.


Continue with The Best Overall Codec Options While Recording on page 18.




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The Best Overall Codec Options While Recording
If you want to distribute your video with a codec other than the TechSmith Screen Capture codec (TSCC), we
recommend you still use TSCC and uncompressed, PCM audio format to record your master video. When the
video is produced in Camtasia Studio, select another video and/or audio codec for distribution (such as a
standard Windows video codec, compressed audio, or a streaming file format) to suite your compression
needs.
TSCC and PCM audio are the default options for recording videos within Camtasia Recorder. However, if
these settings have been changed, you can change the codecs back by following the steps below.


To Change Video Codecs in Recorder
  1. In Camtasia Recorder, click the Tools Options button or choose Tools > Options from the menu bar.
  2. In the Streams tab, disable the Auto configure option.
  3. Click the Video setup button. The Video Compression Setup dialog appears.
  4. Select the desired video codec from the Compressor dropdown menu.
  5. Click OK.


To Change Audio Codecs in Recorder
  1. In Camtasia Recorder, click the Tools Options button or choose Tools > Options from the menu bar.
  2. In the Streams tab, click the Audio setup button. The Audio Format dialog appears.
  3. Select the desired audio codec and attributes from the Format and Attributes dropdown menus.
  4. Click OK.


To Change Codecs after Recording
The Encoding Options screen in the Production Wizard allows you to set the audio and video codecs for the
video you are producing.




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Getting Great Sound in your Recordings
This section contains some hints to make better quality audio recordings and to help you avoid audio
problems before they occur.
However, before you begin recording, make sure that Camtasia Recorder is enabled for audio recording:
1. Open Camtasia Recorder. Choose Start > All Programs > Camtasia Studio 3 > Applications >
  Camtasia Recorder. Or, from within Camtasia Studio, choose
  Tools > Camtasia Recorder.
2. Activate the Audio toolbar by selecting View > Audio Toolbar.
3. Click the Record Audio button     on the Audio toolbar.


Still No Sound?
If you have enabled Camtasia Recorder for audio recording but you are
still are not getting any sound, check the following audio settings within
Recorder.

1. Click the Options button     on the toolbar and choose the
  Volume button under the Streams tab. This will open up the
  Windows Record Control dialog box.
2. Verify that the Microphone is selected as the input within the Microphone section, and that the
  Microphone Volume slider is not at its lowest setting.


I Still Have a Silent Recording
If you have enabled audio recording in Camtasia Recorder and checked the microphone settings, and you are
still unable to record any sound at all, do the following:
   • Check that your microphone is properly connected to the sound card in your computer. It needs to be
     plugged into the microphone jack, not the line in jack, etc.
   • Check to see if you can record with Windows Sound Recorder. Select Start > All Programs >
     Accessories > Entertainment > Sound Recorder.
   • Try a different microphone.
   • Test to see if sound recording is working in another audio application.
   • Try updating/reinstalling the sound card drivers.
   • Try a different sound card.


Continue with the following topics:
Barely Audible Recordings on page 20.
Monitoring your Audio Level as You Record on page 21.
Solving Common Sound Problems on page 22.
Recording Audio from Other Applications on page 24.
Looking at Several Different Kinds of Microphones on page 25.
Tips for Recording Audio in Various Scenarios on page 27.




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Barely Audible Recordings
If you are getting some sound, but your audio recordings are too low in volume, there may be a number of
causes. Some of the most common include the following.


Is your sound card’s recording volume set too low?
You need to adjust the audio level before recording.
1. Open Camtasia Recorder. Choose Start > All Programs > Camtasia Studio 3 > Applications >
  Camtasia Recorder. Or, from within Camtasia Studio, choose Tools > Camtasia Recorder.

2. Click the Options button     on the toolbar to open the Tools Options dialog box.
  On the Streams tab, under the Audio Options section, click the Volume button. This will open up the
  Windows Record Control dialog box.
  Make sure that the Microphone option is selected and that the Microphone Volume slider is up enough to
  allow for sufficient sound.




Are you too far from the microphone?
Try several recordings allowing different distances from the
microphone to choose the right one. You should probably be about six
inches from the microphone—close enough to record full tones but
not so close that other noises interfere.


Are you speaking distinctly and clearly?
To make a good recording, you need to project and enunciate, so that
your voice recording sounds clear and crisp on replay. As an aid in
determining a good vocal level and tone, imagine you are addressing a
small audience in a large room.


Continue with Monitoring your Audio Level as You Record on page 21.




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Monitoring your Audio Level as You Record
While you record audio with Camtasia Recorder, you can monitor the Audio Level to be sure you are
encoding the optimal dynamic range.
   •  The green to yellow range indicate a normal reading.
   •  Orange to red warns that you are close to an over-modulated input.
The best sound quality will occur when the audio level bar is kept in the green to light orange range and only
occasionally enter the red range. That is, try to keep the level bar from filling the entire audio level meter all
the time.
The goal is to keep your input levels as high as possible without exceeding the range of values which can be
stored digitally when encoded. When the Audio Level meter is frequently in the red range, your input level is
too high and the peaks of your waveform become clipped off, resulting in distortion.
The input level also depends on your particular microphone, how close you are to the microphone and how
loudly you speak while recording. By keeping your input levels steady and as high as possible, you will be
encoding the optimal dynamic range.
It is particularly important to record sounds within the green to light orange range if possible if you plan to
later convert 16 bit audio data to 8 bit, or if you plan to compress your audio in a streaming media file. This
assures that you will use the greatest dynamic range possible in the converted file.


Adjusting your Audio Level

To adjust your audio levels, click the Options button     on the toolbar to open the Tools Options dialog
box.
On the Streams tab, under the Audio Options section, click the Volume button. This will open up the
Windows Record Control dialog box. Adjust the volume setting up or down.


Continue with Solving Common Sound Problems on page 22.




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Solving Common Sound Problems
The following gives some information on resolving issues concerning external noise, low quality sound, and
recording conflicts.
Too much External Noise can be Heard
Some audio noise is caused by environmental elements. Background sounds you may not have noticed before
                   may suddenly show up in your audio of your recording. You can
                   eliminate most problems by relocating your recording "studio" to a
                   quieter location. Also, do not forget that most computers make some
                   noise that your microphone might be picking up. The disk drives and
                   fan are potential sources of a low-level noise in your recordings.
                    Hum and whine can also be caused by a “ground loop.” Ground loop
                    occurs where there is more than one electrical path to “ground” for
                    electrical/electronic equipment. Tracing and eliminating the exact
                    source of ground loop can be complicated, but light dimmer switches,
                    motorized appliances, and cable TV outlets are prime culprits.
                    First try disconnecting any unnecessary electrical equipment sharing
                    the same circuit as your computer. Also, disconnect the coaxial cable
                    running to any nearby TVs. If these methods do not help, consult an
                    expert at your local Radio Shack or other electronics retailer. They can
                    offer solutions to help you isolate ground loop interference.


                    Low Quality Recordings
                    The default audio setup for the Recorder is PCM (uncompressed audio)
                    22.050 kHz, 16 bit mono. That should give you good quality audio. If
                    the audio is still low quality, try a different microphone.
                    Additionally, most consumer-quality recording equipment shipped with
computers is relatively low quality (unless you have purchased upgrade accessories). Studio-quality
recordings cannot be made on inexpensive equipment. To improve the quality of recordings, you can upgrade
the components responsible for audio on your computer: microphone, sound card, and speakers.
Better sound comes with a tradeoff, however, as higher quality audio results in a larger Camtasia Studio video
file size. The audio format you specify determines the quality of the video audio track and also affects video
file size.


Large File Size when Recording with Audio
By default, Recorder uses uncompressed PCM audio. That is a good selection for your original recording
because you can later edit the video within Camtasia Studio and not lose audio quality.
It is recommended that you compress the audio during production in Camtasia Studio after you have finished
recording in Camtasia Recorder and have made all your edits.
Within Camtasia Studio, there are many different video file formats to choose from that will allow you to
effectively compress you video. For example, if you produce your video in SWF it will typically be smaller in
size than an AVI. You can try producing in a couple of different formats to find the right size and quality that
you desire.




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Audio Recording Error Message
If you receive an error message relating to audio recording, it might be that another application is using the
sound card to play and/or record audio. Only one application can record audio at a time on your computer.
Some computers with "Full Duplex" sound cards allow one application (for example, Camtasia Recorder) to
record from the microphone, while another application plays sound. In this case, you can even hold the
microphone up to your computer speakers and record what another application is playing. However, many
computers do not have this capability and allow recording only when no other application is playing sound.


The Audio is out of Sync with the Video
Your audio could be out of sync for two reasons.
First, your on-board audio subsystem is not functioning properly. Many Sony VIO notebooks and systems
that have ESS audio may have this problem. The current version of Camtasia Studio will compensate for this
hardware failure. In most cases this problem crops up when the audio stream is longer than the video. To
correct this situation, please download the current version of Camtasia Studio.
Additionally, you can verify this problem by using another application to record audio on the system. Start
recording and note the exact time you start recording. Let it record for 20-30 seconds and then stop recording
and note the exact time that you stopped.
Calculate the time that you recorded for
and then right-click on the WAV file and
select Properties. If the amount of time
that you recorded for does not match the
actual time of the recording session, then
you might be having this problem on your
system.
Second, if the computer is overloaded and
has no resources left, Camtasia Studio can
drop audio. In this case the audio stream
will be shorter than the video.


Continue with Recording Audio from Other Applications on page 24.




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Recording Audio from Other Applications
Camtasia Studio records audio only from the microphone source. If you want to record other audio sources,
such as sound generated by games or other applications, try the following:
  • Check the sound card in your computer. Some sound cards may also have a mixer control that allows
    you to map the audio to the microphone input.
  • Install a sound card that maps the audio to the microphone internally. One such sound card is Sound
    Blaster® Live!, manufactured by Creative®. It places a "What You Hear" input in the Recording
    section of the Windows Volume Control dialog box, allowing for direct recording of audio generated
    by applications. Then all you would need to do is enable audio recording in Camtasia Studio.
  • Record the sound coming from your speakers. Position your microphone about 12 inches at the
    midway point between your computer’s stereo speakers. Test the recording level, and then adjust the
    speaker volume as necessary.
  • Insert a jumper wire in the Line Out and Mic In jacks on your computer’s sound card. If you do, you
    may wish to adjust the microphone again in the Windows Volume Control if the audio is overamped

     or sounds distorted. From within Recorder, click the Options button     on the toolbar to open
     the Tools Options dialog box. On the Streams tab, under the Audio Options section, click the Volume
     button. This will open up the Windows Record Control dialog box. Adjust the volume setting up or
     down.
  •  Camtasia Studio can record sound directly from the sound card, using an application such as Total
     Recorder®, made by High Criteria, Inc. (www.totalrecorder.com). Please note that Total Recorder®
     is not a TechSmith product, and we do not support it or otherwise make any guarantees.


Continue with Looking at Several Different Kinds of Microphones on page 25.




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Looking at Several Different Kinds of Microphones
Choosing the correct microphone for your recording needs can be a time consuming process. Certain types of
microphones produce good recordings in some environments while produce poor recordings in others. It is
important to select the correct microphone to meet your recording needs.