First you need to choose what file type you would like to convert: DVD video or other video file. To do that click the Browse... button and select the appropriate source from the list:

You should choose DVD video file if you have a movie on a DVD disc and:

You should choose other video file type if you have a movie in MPEG-4 format and:

After you press the Browse... button you will be suggested to choose the path of the source file or folder on either your computer hard disk drive or on CD/DVD.

Press Audio track to select audio language (there can be several audio tracks in one DVD, you should select the one you want).

Once the source file path is entered you will see the file information:

• Video parameters:

• Audio parameters:

	Use the Play button to play the source video file to preview it.
	Use the Stop button to stop the source video file while previewing it.
	Use the Slider to find a specific place in the movie while previewing it.

When you are ready to proceed to the next step press the Next>> button to go to Step two.

If you are sure that you want to convert the entire DVD movie or video file then leave checked I want to convert the entire DVD/video movie

and then simply press Next>> to go to Step three.

But usually it is better to try and see the result of so to speak "test conversion": when you choose a small part of a movie and convert it into the selected format. After that if you are satisfied with the output and made sure you can playback it on the chosen device you can convert the whole movie with the same settings or change the settings if you see something wrong. Partial conversion is also useful when you want to cut the scenes from the movie or select only a part of a movie, for instance a music video clip.

To do this mark I want to convert a part of my DVD/video movie:

There are two ways to select the range of the episode you would like to convert:

After you determined the conversion range press the Next>> button to go to Step three.

If you decide to change the source file path to select another movie press <<Back to return to Step one.

If you are going to change some settings of the future output file or of the codec used to convert the video files you should press the Switch to custom mode button thus going to custom mode:

It is possible to return to simple mode whenever you want simply pressing the Switch to simple mode button.

Here you can change any output file settings you like:

See the Advanced Settings section for more detail on different file settings.

If you would like to change some of the specific codec settings press the Advanced... button. See the MPEG-4 codec settings and H.264 codec settings section for more detail on how different codec settings can influence the final output video quality.

After you are satisfied with all the settings in this step press the Next>> button to go to Step four.

If you need to change some settings in the previous step press the <<Back button to return to Step two.

In simple mode the following window will be seen:

It is not too complicated and you need only to point out which device you are going to use to watch the movie after you converted it, type of the storage for the output file and its capacity. The other video settings (audio and video formats, bit rates, video frame rate, frame size, encoding type, audio frequency and number of audio channels) will be adjusted automatically according to the chosen device preset. The conversion speed will depend not only on the source video file type and the chosen conversion range, but also on the chosen device: video will be converted faster for portable devices that have smaller screens with lower resolutions (video with smaller frame sizes), and slower for the devices that have larger screens.

It is also possible to choose the quality-conversion speed ratio from the following presets:

• Best quality - the movie will be converted with the best possible quality but the conversion process will take more time;

• Normal quality/Medium speed - the movie will be converted with normal quality and the conversion process will be a little faster;

• Maximal speed - the movie will be converted at the highest speed possible for the chosen preset at the expense of the quality.

The possible devices presets include:

	-	use this preset if you plan to watch your movie on a portable device with memory stick card that can have the capacity of 512Mb, 1Gb and 2 Gb (you should find out what kind of card you have);
	-	use this preset if you plan to watch your movie on an iPod with hard disk drive that can have the capacity of 5 Gb and 10 Gb (you should see your iPod datasheet to find out what hard disc drive capacity you have);
	-	use this preset if you plan to watch your movie on a portable media player device with hard drive storage. Depending on its capacity you can select the output file size (entering it in digits or using the up and down arrows);
	-	use this preset if you plan to watch your movie on a portable media player device with hard drive storage. Depending on its capacity you can select the output file size (entering it in digits or using the up and down arrows);
	-	use this preset if you plan to watch your movie on a portable multimedia storage device with hard drive storage. Depending on its capacity you can select the output file size (entering it in digits or using the up and down arrows);
	-	use this preset if you plan to watch your movie on a portable DVD player that can playback MPEG-4 (AVI) files. You can save the resulting file on one or two CD-R or CD-RW discs that have the capacity of 650, 700 and 800 Mb;
	-	use this preset if you plan to watch your movie on a portable media player device with hard drive storage. Depending on its capacity you can select the output file size (entering it in digits or using the up and down arrows);
	-	use this preset if you plan to watch your movie on a DVD player that can playback MPEG-4 (AVI) files. You can save the resulting file on one or two CD-R or CD-RW discs that have the capacity of 650, 700 and 800 Mb;
	-	use this preset if you plan to watch your movie on your personal computer or notebook. You can choose file size manually (entering it in digits or using the up and down arrows);
	-	use this preset if you plan to watch your movie on your mobile phone compatible with GSM standards. Select the output file size (capacity) according to the memory stick card capacity that you have - 512Mb, 1 Gb or 2 Gb;
	-	use this preset if you plan to watch your movie on your mobile phone compatible with CDMA standards. Select the output file size (capacity) according to the memory stick card capacity that you have - 512Mb, 1 Gb or 2 Gb.

After you select the device, type of file storage and its capacity press the Next>> button to go to Step four.

If you need to change some settings in the previous step press the <<Back button to return to Step two.

If you would like to change some additional settings press the Switch to custom mode button.

During Step four you can specify the path for the output file and its name:

Here the Path can be selected either from the pull down list or (if you choose Browse) you can specify a folder on your PC where the output file will be created. Note that you will need enough free hard disk space to store the output file. It depends on the file size you selected in Step three (simple or custom mode - 512 to 1500 megabytes). You can also change the File name to any you like or leave it unchanged.

You can also take a look at all the changes made and compare the parameters of the input and the output files:

• Video properties:

• Audio properties:

If you are satisfied with all the parameters press the Start button to start the conversion process.

If you want to change some of the settings press the <<Back button to return to Step three.

The fifth step is the longest in the conversion process. It takes up to several hours depending on different parameters: movie duration, CPU strength and file and codec settings. In this window you can choose to preview the conversion process marking the Preview box (it is marked by default).

You will see the Overall progress in percentage and on the progress bar:

.

The Elapsed time shows how much time has gone since the beginning of the conversion process and the Remaining time shows estimated time left till the conversion finishes.

You can press the Stop button to cancel the process.

After the conversion is over you will be offered to upload your file to the device selected at Step three, or burn it to a compact disc.

Press the Close button to finish the work with AVS DVDtoGO.

[Number of files]   [File size]

File type - the extension used to designate the file so that the codec could identify and decode it correctly. It depends on the device you are going to watch it on and the codec type used to compress the file:

File type can be chosen from the preset list only and cannot be altered.

Number of files - the number of files used to represent the output video movie. It depends on the destination storage capacity:

Number of files can be chosen from the preset list only and cannot be altered.

File size - the size of the output video file. Depends on the destination storage capacity.

Presets include:

File size can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.




Output video parameters

[Bit rate]   [Frame size]

Format - file video format used to encode the movie.

Format setting can be chosen from the preset list only and cannot be altered.

Encoding - number of passes used to perform the movie encoding.

Number of passes setting can be chosen from the preset list only and cannot be altered.

Bit rate - the number of bits transferred per second. The higher the bit rate the better the quality of the resulting video but the output file size also gets larger at higher bit rate values. The value will change automatically to fit the the destination storage capacity taking into consideration all the other changes you make. It is also possible to enter the bit rate manually if you need to do so.

Bit rate setting can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.

Frame rate - the number of video frames displayed every second. Depends on the device used to playback the output video file and the video file format. When transferred over the network also depends on the connection speed.

Frame rate setting can be chosen from the preset list only and cannot be altered.

Frame size (resolution) - the number of pixels that form the video image (horizontally/vertically). The larger the frame size the more processing power is used to encode and decode the video file. Too small frame size causes the quality of the picture to be inapplicable for watching on a large screen. If the video is converted for a portable device that has a small screen with low resolution it is necessary to reduce the frame size to fit the screen resolution, otherwise the device might not be able to playback the output video. One should bear in mind that the conversion with smaller frame sizes takes less time than that with greater resolution values.

Frame size setting can be chosen from the preset list only and cannot be altered.

[Bit rate]   [Channels]

Format - format of the audio component used in the output video file.

Format setting can be chosen from the preset list only and cannot be altered.

Bit rate - the number of data points used to approximate the true wave form. The higher the bit rate the better the quality of the resulting audio but the output file size also gets larger at higher bit rate values. Different types of devices require different bit rate values and might not playback the output file if the bit rate is not appropriate. The value can be chosen from the given presets.

Bit rate setting can be chosen from the preset list only and cannot be altered.

Frequency - sampling frequency specified in hertz. The highest possible pitch in the sound is equal to one-half that of the set sampling frequency.

Frequency setting can be chosen from the preset list only and cannot be altered.

Channels - number of channels in the audio track of the movie.

Channels setting can be chosen from the preset list only and cannot be altered.

MPEG-4 - ISO/IEC open standard for video encoding developed by MPEG (Moving Picture Experts Group). It is characterized by a small output video file size and quite good picture quality even when a relatively low bit rate is used. The most known resulting output when you use MPEG-4 format for compression is the AVI file type which is commonly used in home video. It is coded with XviD, DivX, 3ivx, Nero Digital and other video codecs.

The codec settings can be changed when you press the Advanced... button in Custom mode of the third step. The following tabs of the codec settings window are available:

• Main settings - include Quantization type, Trellis quantization, Profile level, Grayscale enabled, Chroma optimizer, Interlacing encoding, Lumimasking enabled and Quarter pixel.

• Motion settings - include Motion search type, VHQ Mode, Frame drop ratio, Max key interval, Use chroma motion, Turbo mode, Cartoon mode and Global motion compensation.

• B-VOPs settings - include Use B-VOPs, Max consecutive B-VOPs, Quantizer ratio, Quantizer offset.

• Optimization settings - include Automatically detect optimizations, Force optimizations.

[Trellis quantization]   [Profile level]   [Grayscale enabled]

[Interlacing encoding]   [Lumimasking enabled]   [Quarter pixel]

Quantization type - quantization matrices used to convert the movie. Depends on the video bit rate used, movie type and picture quality.

Quantization type setting can be chosen from the preset list only and cannot be altered.

The default value is H.263.

Trellis quantization - an advanced algorithm that lets the codec estimate the quality-size ratio and choose the coding variant based on it. Can improve the quality keeping the file size smaller. At the same time the conversion time increases as compared to the conversion with this setting disabled.

Trellis quantization setting can be either checked or unchecked.

The default value is On.

Profile level - restricts the usage of MPEG-4 tools and limits the encoded bit rate so that the output movie is compatible with hardware decoders. If you are acquainted with XviD codec settings you will find that the Profile levels coincide with the XviD profiles. In the table below you can see which profile allows you to change the specific codec settings and use different quantization types, what maximum resolution, frame rate or bit rate is recommended for every profile.

As can be seen Profile levels "Simple @ L0", "Simple @ L1", "Simple @ L2", "Simple @ L3", "ARTS @ L1", "ARTS @ L2" and "AS @ L2" roughly correspond to the DivX Handheld Profile that is intended to enable the decoding of DivX video content at bit rates and resolutions appropriate for small handheld devices such as mobile phones and digital watches.

Profile levels "ARTS @ L3", "ARTS @ L4", "AS @ L0", "AS @ L1" and "AS @ L3" can correspond to the DivX Portable Profile which will enable high-quality DivX video content for portable video devices, including video-enabled MP3 players and small video playback devices such as PDA.

Profile level "AS @ L4" can correspond to the DivX Home Theater Profile. The specifications for this profile will ensure that DivX Certified home theater devices such as DVD players, set-top boxes, and gaming consoles, can playback all versions of high-quality DivX content.

And Profile level "AS @ L5" can correspond to the DivX High Definition Profile that is intended for any hardware device that can playback high-definition resolution DivX content.

Profile level setting can be chosen from the preset list only and cannot be altered.

The default value is AS @ L5.

Grayscale enabled - lets the codec not to write the information about the color into the frames thus reducing the video frames size in the output video file up to 10%. These saved resources will be used to enhance the output video quality. Can be recommended if you need to convert a black-and-white source video file.

Grayscale enabled setting can be either checked or unchecked.

The default value is Off.

Chroma optimizer - used to produce a better impression of objects edges by reducing the noise around them. It is achieved by interpolating the colors in the dark and bright areas situated near the object edges. As the compression ratio of the picture without the noise is higher the output video will have better quality. Recommended to leave it On.

Chroma optimizer setting can be either checked or unchecked.

The default value is On.

Interlacing encoding - encodes frames as interlaced - only if your source contains interlacing artifacts (i.e. fields instead of progressive frames). There is no guarantee that the picture will be displayed correctly on some devices when this option is enabled. Recommended to use this option to convert fully interlaced source video for watching it on a TV screen only (not recommended when used on a personal computer).

Interlacing encoding setting can be either checked or unchecked.

The default value is Off.

Lumimasking enabled - used to apply more compression to very dark and very bright frames where it cannot be easily noticed by the human eye. At the same time the algorithm releases the resources allowing to decrease the compression of the other frames so the picture looks better. Recommended to turn On if the movie contains lots of very dark or very bright scenes. Not recommended for music video clips.

Lumimasking enabled setting can be either checked or unchecked.

The default value is Off.

Quarter pixel - the codec works with quarter pixels for encoding with a more precise motion compensation. Enabling this option increases the size of auxiliary data so when the bit rate is low the quality can decrease. If you turn the setting on you should bear in mind that the coding and decoding load on the CPU increases heavily and devices with slower CPU's might even not be able to playback the output video files. The compression time with Quarter pixel setting On increases.

Quarter pixel setting can be either checked or unchecked.

The default value is Off.

If you are not sure which settings to use you can press the [Default] button to discard the changes and restore default settings.

When ready press the [OK] button to accept the changes you have made.

[VHQ Mode]   [Frame drop ratio]   [Max key interval]

[Turbo mode]   [Global motion compensation]

Motion search type - decides mostly over the resulting quality at a given bit rate. The codec searches for the motions of the objects in the movie and based on the objects motion estimation compresses the output video. If set to low values, the codec will be faster at the costs of quality for the given bit rate.

Motion search type setting can be chosen from the preset list only and cannot be altered.

The default value is 6 (Ultra High).

VHQ Mode - an algorithm that decides which format will be used to store motion vectors thus reducing the file size. Depends on the Motion search type used - the best compression and the best quality can be achieved when Motion search is equal to 6 (Ultra High) and VHQ mode is equal to 4 (Wide search). Cannot be used together with Global Motion Compensation.

VHQ Mode setting can be chosen from the preset list only and cannot be altered.

The default value is 4 (Wide Search).

Frame drop ratio - allows to set the percentage of frames that don't have any important information and thus can be dropped. It is done to reduce the output file size and preserve the quality. The higher the value the more frames are dropped and the picture might have a "jittering" effect. At the same time the picture quality might increase due to the released resources that are redistributed to enhance the quality of the frames that were not dropped so the Frame drop ratio setting should be picked experimentally. When set to 0 no frames are dropped.

Frame drop ratio setting can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks. Possible values are 0 - 100.

The default value is 0.

Max key interval - maximum number of delta frames (interframes) between two keyframes (intraframes - frames with a very small compression ratio) compulsorily inserted by the codec in addition to automatic I-frames insertion. This is used to reduce the seeking time for fast forward or backward mode when watching the movie. It is necessary for the codec to use I-frames to increase the output video quality as the P-frames (delta frames or interframes) situated between two keyframes are compressed based on the preceding I-frames.

The recommended setting about 300. It is possible to lower the value a little in fast-motion videos although if the value is too small then too many keyframes (I-frames) are inserted and the video cannot be compressed very effectively thus lowering the output video quality. At the same time it is possible to increase the value in videos with a lot of slow-motion scenes as the codec is able to insert I-frames by itself when needed.

Max key interval setting can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.

The default value is 300.

Use chroma motion - an algorithm that lets the codec detect motion in an advanced way and calculate the possibility to additionally compress the output file without the quality loss. The compression ratio can be increased up to 7% thus increasing the final quality but the conversion speed will be much lower.

Use chroma motion setting can be either checked or unchecked.

The default value is On.

Turbo mode - lets the algorithm estimate the motion for b-frames and quarterpel faster.

Turbo mode setting can be either checked or unchecked.

The default value is Off.

Cartoon mode - special possibilities for motion estimation when converting cartoons (animated pictures).

Cartoon mode setting can be either checked or unchecked.

The default value is Off.

Global motion compensation - helps while coding the objects that only change their size or place in the picture but keep static (for instance, when the camera zooms in or out or moves shooting the panoramic view). It is recommended to use this option when converting movies with nature views and alike. The compression ratio can be increased up to 3% (the released resources will be used to enhance the output video quality) but the conversion and decoding speed will be lower. Most effective for compressing the videos with greater resolution. Cannot be used together with the VHQ Mode.

Global motion compensation setting can be either checked or unchecked.

The default value is Off.

If you are not sure which settings to use you can press the [Default] button to discard the changes and restore default settings.

When ready press the [OK] button to accept the changes you have made.

[Max consecutive B-VOPs]   [Quantizer ratio]   [Quantizer offset]

Use B-VOPs - an option that allows the codec algorithm to use so called bidirectional frames that are much smaller in size than usual frames and are predicted based on the frames before and after them. They let the codec increase the compression ratio without quality loss.

In video compression three types of frames can be used: I-, P- and B-frames. I-frames are the frames with a very small compression ratio. They are also called keyframes (intraframes) - see Max key interval. When watching the film the navigation is done using the I-frames. Between two I-frames the codec uses a succession of P-frames (delta frames or interframes), which have a much higher compression ratio, for instance:

and so on. To further increase the video compression ratio, B-frames were introduced. They are inserted between two less compressed frames - I-frames or P-frames, so that the succession of the frames in the video file looks like

Compression ratio for the B-frames is the highest among all the frames as they are compared with the previous and the following frames and only difference between them is written into B-frames. The released compression possibility is redistributed between the I-frames and P-frames allowing to compress them less but at the same time keeping the file size smaller. And though the quality of B-frames is worse than the quality of P-frames and I-frames, the picture quality remains quite good due to the reduction of compression of the latters.

It is recommended to leave the Use B-VOPs setting On.

Use B-VOPs setting can be either checked or unchecked.

The default value is On.

Max consecutive B-VOPs - maximum number of sequential bidirectional frames in the video stream. The best result might be achieved when bidirectional frames and interframes are interleaved thus the Max consecutive B-VOPs number is equal to 1. If you set this number to 0 the result will be the same as to uncheck the Use B-VOPs setting. At higher values the movie picture might flicker but you might try to change the value to see the result for yourselves.

The default value is 1.

This value is for information purposes only and cannot be changed.

Quantizer ratio - the ratio used to calculate the bidirectional frames quantizer according to the following formula:

B-frames quantizer = [(Quantizer of previous P-frame + Quantizer of following P-frame) * (B-frame quantizer ratio)/200 + (B-frame offset/100)].

As can be seen, if you increase the default value the ratio of bidirectional frames compression will be also increased decreasing the ratio of compression of the other frames thus improving their quality. At the same time the quality of bidirectional frames will get worse so you should check the output result. If the default value is decreased the ratio of bidirectional frames compression will also decrease thus increasing the compression of the other frames and reducing their quality or increasing the size of the output video file which is not recommended.

The default value is 150.

This value is for information purposes only and cannot be changed.

Quantizer offset - the offset used to calculate the bidirectional frames quantizer. It is not recommended to change this value although you can try to change it to compare the results.

The default value is 100.

This value is for information purposes only and cannot be changed.

If you are not sure which settings to use you can press the [Default] button to discard the changes and restore default settings.

When ready press the [OK] button to accept the changes you have made.

[Automatically detect optimizations]   [Force optimizations]

Automatically detect optimizations - this setting lets the codec automatically detect the CPU type and the instructions set it can use best.

It is recommended to leave this setting On.

The default value is On.

Force optimizations - this setting lets you override the codec internal CPU detection and use the instructions set you consider necessary.

Usually, you should leave this on auto detection. If you get weird crashes or strange results, you might first try to disable SSE + SSE 2, if still nothing changed disable 3DNow! + 3DNow! 2 and so on.

This is only for situations where the wrong CPU extensions get used and produce erroneous output.

3DNow! and 3DNow! 2 belongs to AMD (Advanced Micro Devices), while the rest are Intel Architecture technology.

It is not recommended to change this setting.

The default value is Off.

If you are not sure which settings to use you can press the [Default] button to discard the changes and restore default settings.

When ready press the [OK] button to accept the changes you have made.

H.264 - H.264, or AVC, for Advanced Video Coding, is a digital video codec standard which is noted for achieving very high data compression. It was written by the ITU-T Video Coding Experts Group together with the ISO/IEC Moving Picture Experts Group as the product of a collective partnership effort known as the Joint Video Team. The intent of the H.264/AVC project was to create a standard that would be capable of providing good video quality at bit rate that are substantially lower (e.g., half or less) than what previous standards would need (e.g., relative to MPEG-2, H.263, or DivX and XviD).

The codec settings can be changed when you press the Advanced... button in Custom mode of the third step. The following tabs of the codec settings window are available:

• Rate Control settings - include Bitrate, Quantization Limits, Scene cuts.

• MBs and Frames settings - include Partitions, B-Frames

• More settings - include Motion Estimation, Miscellaneous options

[Quantization Limits]   [Scene cuts]

The Bitrate section comprises the following codec parameters:

• Keyframe boost controls how much the quality of key frames (I-frames) is boosted as compared to the other frames (P-frames). Please, see the B-VOPs section of the MPEG-4 codec for more detail on different frame types used in video coding. The boost gives I-frames some extra quality, so frames predicted from them will also be of better quality, leading to a better visual impression. The higher the value, the more quality is given to the I-frames and the less to the other frames. You can try the higher values for low-bitrate and low-quality encodes or lower values for bright, continuously fast-moving videos where the background is frequently changing. The possible values vary from 0 to 70. The default value is 40.

• B-frames reduction controls how much the quality of B-frames is reduced as compared to the other frames (P-frames). This cut in B-frame bitrate is hardly noticeable to the human visual system because B-frames are used inconspicuously in between other frames to more efficiently recreate the video's motion. It is possible to lower this value a little for high-bitrate/low-quantizer video thereby ensuring a more uniform quality to details, motion and the video as a whole. For animated content (cartoons, anime), you might use higher values. The possible values vary from 0 to 60. The default value is 30.

• Bitrate Variability controls the extent to which the codec can variate the quality throughout the movie at the bitrate specified. The lower this option is set, the more unstable and erratic the quality changes can become. The higher this setting is, the more equal the quality becomes, producing a video with more stable quality. The possible values vary from 0 to 100. The default value is 60.

All the Bitrate settings can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.

The Quantization Limits section comprises the following codec parameters:

• Min QP sets the lowest quantizer your video can attain at any point. Very high values are not recommended unless you plan video with an immensely high bitrate and low resolution. The possible values vary from 0 to 51. The default value is 10.

• Max QP sets the highest quantizer you video can reach. It is strongly recommended leaving it where at the default value of 51. The possible values vary from 0 to 51. The default value is 51.

• Max QP Step controls how how much the quantizer can change between two consecutive frames. Setting this value too low forces the codec to switch quality levels slowly, which can be devastating to the compression of certain scenes which, for example, could suddenly use a lower quantizer to maintain similar visual quality. Setting it too high can lead to conspicuous jumps in quality. The possible values vary from 0 to 50. The default value is 4.

All the Quantization Limits settings can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.

The Scene cuts section comprises the following codec parameters:

• Scene Cut Threshold determines how much a frame needs to change before being considered a scene change by the codec. The higher the value, the less sensitive scene change detection will be. For dark videos you might want to decrease this value so as to let the codec more accurately determine scene changes. As a more general rule, videos with more subtle scene changes need a higher scene cut threshold and bright high-contrast videos with very prominent scene changes might actually be reason to attempt to set a lower threshold. The possible values vary from 0 to 100. The default value is 40.

• Min IDR-frame interval sets the minimum number of frames between two keyframes. If this value is set too high, too much time will go by without the codec detecting a scene change and implementing the necessary keyframe. Setting it too low can result in a waste of bitrate and sometimes flickering. The possible values vary from 0 to the number of the frames in the video. The default value is 25.

• Max IDR-frame interval sets the maximum the minimum distance between two keyframes. Setting this too low can result in an oversaturation of key frames, possible flickering, and general bitrate waste, reducing overall quality. Setting this too high can result in seeking issues, and any artifacts/encoding flaws during the time between key frames will remain on the screen longer. The possible values vary from 0 to the number of the frames in the video. The default value is 250.

All the Scene cuts settings can be altered manually to suit your personal needs - you can enter the values using the keyboard or with the mouse clicks.

If you are not sure which settings to use you can press the Restore Defaults button to discard the changes and restore default settings.

When ready press the OK button to accept the changes you have made.

[B-Frames]

The Partitions section comprises the following codec parameters:

The partition search and decisions increase the accuracy and thus the quality and compression efficiency of the codec, enabling higher quality output. As a general rule, the more searches types of searches the codec performs on the visual information, the more accurately and efficiently it can predict and encode them. Disabling any partition search and decision options will speed up the encoding process at the expense of the quality.

The 8x8 Transform feature is a very powerful compression technique which acts upon larger blocks of visual information and enables the usage of other high-quality partition options such as the 8x8 Intra search which would otherwise be unusable without the 8x8 Transform. Both of these options increase quality to a significant degree, but the usage of the the 8x8 Transform would make your video High Profile AVC compatible and would break the encoded video's compatibility with Main Profile AVC. Thus you should make sure your device supports High profile AVC, otherwise you might not be able to playback the resulting output video file.

All the Partitions settings can be either checked or unchecked.

The B-Frames section comprises the following codec parameters:

• Use as reference allows a B-frame to reference another B-frame. Checking this setting might increase quality slightly because these B-frames can be predicted from one another instead of being limited to the P-frames around them for prediction and at the same time the time of the conversion will also increase. This setting should be activated when using more than 2 consecutive B-frames (See the Max consecutive setting below).

• Max consecutive indicates how many B-frames will be used consecutively. You can use up to 5 consecutive B-frames, but using 2-3 is the most sensible choice. The possible values vary from 0 to 5. The default value is 0.

• Adaptive activates adaptive use of B-frames. Without this feature, the codec will always put as many B-frames in a row as set in the Max consecutive field.

• Bias lets the codec increase or decrease the probability that B-frames are being used. The higher this number, the more frequently B-frames will be dropped in. Setting this parameter to 100, for instance, will force the codec to use the maximum number of B-frames specified in the Max consecutive box - it will be the same as uncheck Adaptive check-box. Setting this to -100 will mean that almost no B-frames are used. For most videos, the optimal number of B-frames will be chosen at Bias value of 0. The possible values vary from -100 to 100. The default value is 0.

• Bidirectional ME parameter allows the codec to predict some B-frames using motion before and after them. This increases quality of the output video.

• Weighted bipredictional setting allows B-frames to be predicted more heavily from one P frame or another. It results in more accurate and efficient B-frames, therefore increasing quality.

• Direct B-frame mode allows B-frames to use predicted motion vectors instead of coding the actual motion, thus saving space and increasing compression efficiency. This setting indicates how motion vectors for B-frames are derived: Spatial uses neighboring blocks in the same frame, which may result in a higher PSNR (it can be used for animated content as it better handles inconsistent motion jumps), whereas Temporal makes use of neighboring frames - which many people perceive as higher quality (better used for real-life content with fluid motion).

If you are not sure which settings to use you can press the Restore Defaults button to discard the changes and restore default settings.

When ready press the OK button to accept the changes you have made.

[Motion Estimation]   [Miscellaneous options]

The Motion Estimation section comprises the following codec parameters:

• Partition Decision parameter controls the precision of the motion estimation process. The selection menu contains a list of 7 options, arranged from the least quality 1 (Fastest) to the highest quality 6b (RDO on B-frames) options. It is strongly recommended to use the options below 5 (High Quality) only in case the speed is crucial and the quality is expendable. In all the other cases the values of 5 (High Quality), 6 (RDO) and 6b (RDO on B-frames) should be used. The higher the value, the better the quality at the expense of the conversion speed.

• Method indicates in which direction the motion estimation search is performed. The better the method, the higher the likelihood of the codec finding and accurately recording motion, thereby increasing the compression quality and efficiency. It is recommended to use either Hexagonal search for slower machines or Uneven Multi-Hexagon for more powerful configurations. The Exhaustive Search can be used only on extra-powerful computers as it decreases encoding speed dramatically.

• Range specifies the motion search range in pixels. The higher the range, the more pixels will be analyzed, which is paid by slower encoding time. This parameter is only used together with Uneven Multi-Hexagon and Exhaustive Search motion search methods. The possible values vary from 0 to 64. The default value is 16.

• Max Ref. frames indicates how many previous frames can be referenced by a P-frame or B-frame. The higher is this value, the better but the coding process gets slower at the same time. The possible values vary from 0 to 16. The default value is 0.

• Mixed Refs option offers the codec greater freedom to make references on a smaller scale when checked. Requires the Max Ref. frames value to be more than 1 to be turned on.

• Chroma ME uses the color information in the video's chroma plane to estimate motions, which increases both the accuracy and visual quality of motion estimation. This almost always leads to a significant quality increase, especially with animated material. It can be recommended to switch this option on.

The Quantization Limits section comprises the following codec parameters:

• Threads should be equal to the number of encoding threads that can be used in the encoding process. The number of threads should correspond with the number of processor cores the computer has. Each single Hyper Treading processor can be counted as 2 threads. When not sure how many cores your computer has, or whether or not it has HT, it's safe to keep this setting at 1. This option speeds up the encoding process on multi-core machines. The possible values vary from 1 to 4. The default value is 1.

• CABAC - Context Adaptive Binary Arithmetic Coding - is a feature that allows syntax elements of the video stream to be predicted by context. Basically, it increases compression efficiency at no quality loss (10-15% varying by video and by bitrate), though the decoding speed can slow down. This option should be unchecked only if you plan to playback the output video on a portable device with a slow processor. It is On by default.

• Noise reduction option switches on and off the image noise prefiltering. The value of 0 turns this option off, the other values (1 to 65535) turn on the filter of small image noises. The possible values vary from 0 to 65535. The default value is 0.

• Trellis is an advanced algorithm that lets the codec estimate the quality-size ratio and choose the coding variant based on it. Can improve the quality keeping the file size smaller. At the same time the conversion time increases as compared to the conversion with this setting disabled. It is only available if the CABAC setting is on.

• Deblocking filter option switches on or off the in-loop deblocking filter. Enabling this feature also increases the conversion time.

• Strength determines how strong the deblocking effect needs to eliminate the blocks where the Threshold identified them. The possible values vary from -6 to 6. The default value is 0.

• Threshold determines how much of the material actually needs to be deblocked. The higher the value is set, the more of the video will be perceived as blocks, so the more the deblocker will act upon. The possible values vary from -6 to 6. The default value is 0.

If you are not sure which settings to use you can press the Restore Defaults button to discard the changes and restore default settings.

When ready press the OK button to accept the changes you have made.