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Make a lossless snippet of your video

MOV/MTS/M2TS to MP4

Audio to AAC

Fix Video Orientation

Convert multiple VOBs to a Single MPG

Convert a video to constant framerate

Crop and Resize a widescreen movie from a

4:3 DVD

Introduction

AVIDemux is a video processing program with lots of features hidden under the hood, but it’s main advantage is that it can convert video and audio independently and, in some scenarios, without recoding. This is good because often we just need to change a file extension/container eg MOV>MP4, or audio from AC3 to AAC, or fix the orientation of a video. Other programs, such as Handbrake, will re- encode the video, creating generation-loss, as well as possibly being time-consuming. Listed above are some scenarios where AVIDemux is an ideal tool. It also has many other features.

Download and Installation

These instructions are for the 64bit version. The 32bit version is “similar”. Download AVIDemux from here: https://www.videohelp.com/software/AviDemux You can either download the normal, installer version, or the portable version that does not install. Note that the version numbers shown here may not be the latest version. The portable version does not install on your computer, it downloads as a ZIP file which must be unzipped; then the Avidemux.exe file can be run from inside that unzipped folder. To set up the portable version, follow these steps: 1. Download the Portable version (the download will be a single ZIP file). 2. Save the ZIP file in a folder of your choosing. When the file is unzipped, a folder containing the program files will be created inside this folder. 3. On the ZIP file, right-click and choose Extract All… 4. On the next screen, click Extract. The AVIDemux folder will be extracted from the ZIP. 5. To start the program, open the AVIDemux folder and double-click on the AVIDemux.EXE file.

Make a lossless snippet of your video

Note: this procedure can also be used losslessly cut out parts/edit/trim your video. You may be asked to provide a short snippet of your problem video so others can analyse it. The trick is to provide the snippet in the original format, not re- encoded. If you use Handbrake (for example), your video will be recoded. Using AVIDemux’s Copy-Copy feature, you’ll get a non-recoded, lossless, “original” snippet.

Set up your output options

Open the file. Adjust the options down the left side as follows: Video Decoder: Leave as-is. Video Output: Put on “Copy”. Audio Output: Put on “Copy”. Output Format: In the dropdown, choose the appropriate “muxer” or container/extension that is the same as your file. If your original file is AVI, choose “AVI Muxer” from the droplist; if it is MP4, choose “MP4 Muxer”. For an MPEG file, choose “MPEG-PS Muxer”.

Mark your snippet

On the timeline at the bottom of the monitor, choose a short section to export as your snippet. Position the Play marker, then use the A and B buttons to mark out a short section. You can also drag each end of the selection box. Be aware that you will not be able to choose the exact frame for the A and B points due to the nature of the “copy”. Lossless copying can only be made on I-frames. For MP4s/MOVs/MPEGs, choose around 30 seconds of video. For AVIs, choose around 10-15 seconds. This will keep the snippet file size down to a manageable level for uploading to forums such as VideoHelp, which has a 500mb limit. Your screen should now look like this: Now you can save your snippet by clicking File>Save or by clicking on the icon on the top menu bar. In a short time, you’ll have a snippet of your original file with unaltered/non-recoded video and audio.

MOV/MTS/M2TS to MP4

Your video editor may not open some types of these files. In some cases, it is simply the file header, and not the underlying codec, which is causing the problems. For example, all these file types probably have AVC/H264 as their video codec. AVIDemux can convert them to a more friendly type, MP4, without recoding, by keeping the underlying video codec intact. This process can also be used for TS files with the AVC/H264 codec. Open the file. Adjust the options down the left side as follows: Video Decoder (if shown): Leave as-is. Video Output: Put on “Copy”. Audio Output: Put on “Copy”. If the file has multiple audio tracks, you can select the desired track in the Audio>Select track menu. Output Format: In the dropdown, choose “MP4 Muxer” That’s it. Your AVIDemux screen should look like this: Now set the conversion running by clicking File>Save. In a short time, you’ll have an MP4 file with unaltered video and audio that your editor should accept.

AC-3 Audio to AAC

Open your file Video Decoder: Leave as-is. Video Output: Leave as Copy Audio: on the main Audio menu, click Select Track and untick the tracks you don't want (try using track 1 to start) Audio Output: choose AAC (FDK) Audio Configure: bitrate to 192 Audio Filters: Resample to 48000 Output format: MP4 Muxer Click the Save button and in a short time you should get an MP4 video with AAC sound.

Fix Video Orientation

Note: I have discovered a scenario where AVIDemux will not rotate the flag losslessly, so this may not work. You may have to re-encode the file to rotate it. In these days of smartphones, when hitting the Record button in Portrait then quickly flipping the phone to Landscape, we sometimes find the video orientation isn’t flagged correctly for your video editing program. While I know videos can be flipped on the timeline, I have been in situations where that is unwieldy or doesn’t “hold” when other effects are applied, and it is easier to just flip the video, external to the editor, then bring it in in the correct orientation. AVIDemux is able to change the orientation flag without recoding the video. Analyse: Open your file. From what you see in the AVIDemux main window, determine the rotation required to make it right. Ignore what the file looked like in your editor or in Windows Explorer. Video Output and Audio Output: Leave both on “Copy” Output Format: Set MP4 Muxer Output Format Configure button: Set the rotation to what you want it to do in the AVI Demux window (not the Explorer or video editing program display). If the video looks correct in AVIDemux, no further setting is required, just save it using Save As. Save As: AVIDemux will reset the rotation flags so that the video presents correctly but otherwise not re-encode the file. An example: My video editor imports a video looking like this: When opened in AVIDemux, it looks like this: As the orientation is displaying correctly, simply Save As and your video’s flag will be set to Landscape. If it displays incorrectly in AVIDemux, apply the appropriate rotation (via the Configure>Rotation button) only to make it look correct in AVIDemux, not the other program, then Save As.

Convert multiple VOBs to a Single MPG

Note: This process will not save any subtitles. AVIDemux will join together sequentially-named files such as VOBs that have been ripped from a DVD onto your hard drive such as: In this case, the sequential VOBs are VTS_01_1.VOB, VTS_01_2.VOB, VTS_01_3.VOB, VTS_01_4.VOB and VTS_01_5.VOB (being the main movie of this DVD). For copyrighted DVDs, you’ll have to “rip” the DVD folders/files to your hard drive using appropriate ripping software. For non-copyrighted DVDs (eg home videos), simply insert the DVD into your DVD drive, then “open” the DVD in Windows file explorer (on the DVD drive, right-click “expand” to display the VIDEO_TS folder). Copy the VIDEO_TS folder across to a suitable system hard drive. After the VIDEO_TS folder is on your hard drive, proceed as follows: Click File>Open Click on the first file of the main movie sequence ie VTS_01_1.VOB, click Open and AVIDemux will present this message: This signifies that AVIDemux has detected the other files in the VOB set, being 01_2, 01_3 and so on. Click “Yes”. The combined VOBs will be shown as the movie: With the combined files on the timeline, configure the export: Video Decoder: Leave as-is. Video Output: Since VOBs are a subset of the MPEG 2 format, no change is necessary here so leave as-is ie “Copy”. Audio (Main Menu Tab)>Select Track: Some DVDs have multiple audio tracks which may not be compatible with the MPG output format. On the main Audio menu, choose “Select Track” and tick only Track 1 (which should be the main audio track). Audio Output: If you don’t need to change the audio format, then leave this on “Copy”. If you do need to change the audio format (say if your video editor cannot open files with AC3 audio) then, back on the left hand side now, in the Audio Output droplist choose MP2 (lav). Audio Output Configure: Change the MP2 bitrate to at least 224. Audio Output Filters: Tick Resampling and type in 48000, tick Remix and choose “Stereo”. Output Format: From the dropdown, choose Mpeg-PS Muxer (ff). That’s it, now do a File>Save (or click the Save Video button) and in a short time you’ll have a single MPEG 2 file that you can play as-is in all players, or you can import into a video editor for further editing. Only the audio will be recoded (if you have chosen to do so); the video will be losslessly processed into an MPEG 2 file. You can, of course, save/export your video in some other format, such as MP4, using the video and audio droplists, configure and filter buttons.

Convert a video to Constant Frame Rate

Sometimes, Variable Frame Rate (VFR) videos, such as those from smartphones, can trouble video editing software, including errors on import and audio desynchronisation. Converting the video to Constant Frame Rate (CFR) may resolve this issue. MediaInfo can be used to analyse a file’s data, and in particular, the (variable) frame rates: If the Min and Max frames rates are wildly different, it may beneficial to re-encode the video to CFR. To convert a video from VFR to CFR, open the file and select File>Information. Note the frame rate and the Average Bitrate: Now, set up AVIDemux to change to CFR. Down the left side:

Video Output

From the droplist, choose an appropriate encoder (not “Copy”). Click Configure and in the Max Bitrate box, enter the Average bitrate from the Properties box. Yes, “Average” and “Max” doesn’t make sense but it works (the aim being to encode at a bitrate similar to the original file). Click OK. Click Filters. In the Available Filters list, double-click Resample FPS. In the New Frame Rate box, set the desired frame rate eg 59.94 and click OK and Close.

Audio Output

Set this to Copy.

Output Format

Set this to match the video codec chosen in Video Output above. For H264, select MP4 Muxer. Lastly, File>Save to save your file as CFR.

Crop and Resize a Widescreen Movie from

a 4:3 DVD

Introduction

Note This procedure will remove the duplicated 5th frame from a 29.97fps video, returning the video to the original film speed of 23.976. It will not de-telecine a telecined movie. Some widescreen movie DVDs are formatted to play on a 4:3 screen, which means that when they are played on a 16:9 screen, the 2.55:1 movie is unnecessarily scaled down, like this: This width is being constrained by the burnt-in letterboxing black bars at the top and the bottom of the video. The dotted outline depicts the 4:3 frame from the DVD. To make the video display show full width, the top and bottom bars need to be cropped away. This will allow the video to expand vertically and sideways to fill the 16:9 screen. To achieve this, the video is cropped and resized, then exported.

Determining the actual movie size/ratio

The first step is to determine the actual dimensions of the movie. If it’s from a DVD, the frame will be either 4:3 or 16:9. The movie itself could be anything; the above movie is 2.55:1, but other common movies are 1.85:1, or 1.66:1 or even 16:9 (1.777:1). Some ways to tell are from the DVD box or by opening the video in a player eg VLC player, set the frame to 4:3 or 16:9, whichever is most- obviously correct (Video>Aspect Ratio). In this case, at 16:9, the movie is obviously stretched too wide, so the DVD frame must be 4:3. When you have the frame displaying correctly, measure the actual movie dimensions on the screen. Dividing the width by the height will give you the movie’s frame ratio eg 2.55:1. Remember that number.

Video Output

Open the video in AVIDemux.

Droplist

Choose a suitable encoder for your final file. A good codec is 264. If you have an NVidia graphics card, that will give a good encoding speed.

Configure

The settings for bitrate control RC Mode are entirely up to you. Most use Constant Quantizer (~18). I prefer Variable bitrate. For this example, I am going to use Variable Bitrate mode and a bitrate of 8000 with a max of 20000 (the original DVD file is 6000), like this: Click OK out of the configure screen, then click Filters.

Filters

Click on Transform in the left column, then in the centre, DC Crop: After the DC on Crop, the crop screen appears: Note that I have put the Lock Aspect Ratio droplist to Do Not Lock. This because AVIDemux does not have a preset for 2.55:1. The common ARs are in the droplist so choose one of those if that suits your movie. It makes cropping easier. Using the top-left and bottom-right corner handles, drag the crop box over the video to cover the unwanted areas. If you have set “Lock Aspect Ratio”, only the bottom right handle will work. Drag the crop box around with the left mouse button. To make finding the edges easier, use the play marker at the top to drag through the video to find a frame that is bright enough to show the edges clearly. Always crop in even numbers to avoid upsetting the interlacing (if any). After my cropping, this is the result (ignore the distorted picture: AVIDemux doesn’t show the correct display here): Click OK, then in the centre filter list, DC swsResize. Here we set up the resize to a normal frame size of 1920 pixels wide. Remembering that our movie is 2.55:1, that means that for a width of 1920, the height must be 752 (rounded to even; 1920/2.55). These are the numbers we use to resize: Note I have unticked Lock Aspect Ratio. After entering the dimensions, the resultant AR is shown at bottom right. Click OK and the Close to return to the main screen.

Audio Output

Some videos have multiple audio tracks. On the Audio menu, untick unwanted tracks. I normally just have track 1 ticked. You should be able to leave the Audio Output on Copy. If AVIDemux protests about the audio when saving the file, put the audio output on AAC (Lav) and on the Configure button, set the bitrate to 192kbps. On the Filters button, set the sampling rate to 48000.

Output Format

Choose an appropriate file format. I normally use MP4 Muxer. That’s it. Save your video and you will (should!) have a correctly-proportioned video that will have no side bars if it’s a widescreen movie, or no top and bottom bars if it is a 4:3 movie. Naturally, because, in this case, the movie is 2.55:1, it will play with bars on top and bottom (letterboxed) but at least it will display laterally at full screen, in the correct proportions.