mp3DirectCut Manual

Introduction
Quick guides
Basic settings
Navigation
Audio editing
Prelisten and save
Pause detection
Recording
More features
Project files
Keyboard shortcuts
Command line options
Frequently Asked Questions

Introduction

mp3DirectCut is a frame based editor for MPEG audio (Layers 2 and 3) and AAC (LC). Frame based means: Instead of PCM samples it works on the encoded frame structure. Each frame keeps a number of samples. You can cut, copy, paste, trim, append and for MP3 also change level and fade without re-encoding. This makes mp3DirectCut very fast and prevents loss of audio quality. The program provides easiest navigation even on large files (up to 4GB) and gives you a very fast visualisation of the compressed audio data. It can handle Cue sheets allowing to split a file at cue positions. Additionally you can directly record and encode MP3 from your audio input devices.

Quick guides

General usage

Open a file: File > Open (also possible: Drag+drop or file by command line). Prelisten with Play / Stop or Spacebar. Navigate through the track: Cursor left/right, Page up/down, Mousewheel, click into total view area (below audio graph) or Scrollbar.

To see the meaning of the buttons in the lower area and in the toolbar, please read the tooltips of the buttons.

Cutting a part of audio

Mark a selection either by adding with the left and adjusting with the right mouse button. Adjusting also works over long distance after seeking a new position. Or use the buttons Set begin and Set end (or the keys B and N) to set the beginning and the end of the selection to the current play position (yellow line). To prelisten the cut press the Prelisten AS CUT button (or F9). Adjust the selection with the right mouse button or the keys 1-4. To cut press the Cut/Cue button in the lower panel (or the Del key). Use normal play to control the Cut. Save the file: File > Save all audio.

Extracting a part of audio

Make a selection as for cutting (see above). To prelisten the range boundaries you can use the buttons Prelisten FROM BEGINNING and Prelisten TO END (or the keys F6 and F7). Adjust the selection as described above. Save the selected range: File > Save selection.

Split into multiple files

To each wanted split position add a point selection: left click (no drag) into the audio graph. Press Cut/Cue (or the Del key) to create a cue. A split point (cue) must show a dotted line! If a zero length cue does not show a dotted line, the "Cue flag" is missing. Move the play cursor right to it and press Ctrl+Q. To jump between cues, press >I or I<. Cue sheets are text files containing index positions to a linked audio file. You can open Cue sheets completely or only load the cues by the corresponding function in the Special menu. To split the track, select File > Save split. Select a destination folder and edit the filename creation template.

Fade in/out

Point to the position where a fade should end (fade in) or start (fade out). In the Edit menu choose Simple fade or Two stage fade. Adjust the fade by dragging the grey handle(s): left button up/down for level, right button left/right for position. For creating fade curves you can add more cues. For AAC and MP2 gain adjustment is not possible.

Add, move, remove a cue

Click once (not drag) into the audio to create a cue. The vertical line must be dotted. Press Cut/Cue (or the Del key). Move the cue by dragging the grey handle with the right mouse button. Remove a cue: move to the right of it, and press Edit (or E). Convert to a cue: move to the right of it and press Ctrl+Q (Cue flag).

Basic settings

To play files, the program uses decoder libraries. For MP3 this usually is the system provided ACM Codec (Windows since XP contains it by default). The mpglib.dll can be used for MP2 playing and alternatively for MP3. It must be in the program folder or in the system path (e.g. Windows folder). For playing AAC you need the free libfaad2.dll (also working: a renamed ff_libfaad2.dll from ffdshow) in the program folder or system path. The libfaad2.dll must be 32 bit and also needs the MSVC 9.0 runtimes (usually present in newer Windows versions). For demuxing AAC from MP4 you can tell the program where to find the ffmpeg.exe from the free FFmpeg.

Switch to your prefered MP3 decoder in the Devices settings (Settings > Configure > Decoder). Under Settings > Devices in the Output section you can select a Wave device and adjust the amount of frames being decoded to each play buffer between "fast" (1 frame) and "reliable" (8 frames). On slower machines set a higher value. For a fast response of the graphics select a lower value. For MP3 recording you also can set the input device on this page and enable level activated recording.

The program language can be set in the Operation Tab (Settings > Configure > Operation). In the list select your language if present. The language files must be in a sub directory "Languages" of the mp3DirectCut folder. If no language is selected or found, the program looks also into its own folder for one (!) language file. So you also can enable your language without keeping the subfolder (but then it won't appear in the list).

As the drawing rooutines are not optimized, Fullscreen view is not recommended. It takes more CPU - without any information benefit, because the resolution of the MPEG graph is much lower than the display resolution on fullscreen.

Navigation

mp3DirectCut is designed to handle large files, and there are many ways to reach a position:

Scrollbar
With the slider you can move along the audio.

Total view
The toal view directly below the audio graph shows an overview of the whole audio, including selection, play position and edit ranges. You can directly jump to any file position by clicking or dragging here.

<< < > >> and keys: Left/Right and Page up/down
These buttons/keys are user definable. You can set the amount of frames to skip back/forward in the settings. For 44 kHz tracks, 38 frames means about 1 second, 383 skips 10 seconds.

Mouse wheel
No key: slow scroll, Shift: fast scroll, Ctrl: zoom, Shift+Ctrl: volume.

Ctrl+Mouse
If you hold down the Ctrl key while clicking into the audio graph, the cursor jumps to the pointed position.

List menu, selection, edit points
There are also buttons to jump between the edit points which you can also reach by the List menu. Beginning and end of the selection can be reached by two more buttons (or the up/down keys).

Step single frame
To move a single MPEG frame backwards or forward, use the keys Shift+Left/Right.

Position field
You can enter a position by time or percentage into the edit field and apply the value by pressing Enter or Tab.

Audio editing

General

Each time you cut or set a cue or level point, your track will be devided (virtually) into more parts. Every edit point is the beginning of a new part. The List menu shows each present part and its function.

Like in other editors, editing begins by making a selection. A selection can be a range or only a single position point (dotted line!). Ranges can be used to cut, copy or also exporting. A point selection is for creating cues or points of level change.

Create selection

Buttons  Set begin  and  Set end 
These buttons set the beginning or the end of the selection to the current play position.

Mouse
You can point/drag a selection by using the left and the right mouse button. How the buttons behave can be set in the preferences: Method 1: Left button sets the beginning of the selection (by clicking or dragging), the right button sets the end. Method 2: Left button makes a new selection and enlarges it. The right button moves beginning or end (depending on which is nearer). Default is method 2.

To make a large selection, simply move to the destination and complete it there (e.g. with the right button). It is not possible to drag a long selection by moving the mouse over the window borders.

Selection field
You can enter beginning, end or length of the selection by numbers. Take care not to delete the symbols, otherwise the values cannot be read correctly.

Trim the selection
Fine adjustment of the selection can be done with the keys 1 to 6: 1/2 = beginning, 3/4 = end, 5/6 = whole selection.

The buttons Cut and Edit

The Cut/Cue button splits the current audio part into two parts. If there was a selection range, it will be cut. If the selection was zero length, the split point can be used to create a volume change (see below) point or a cue.

If a split point should work as a cue (e.g. for splitting the audio), its Cue flag must be set. The program sets it automatically on creating a split point or on loading a Cue sheet. Edit points with Cue flag are shown as dotted line. To set or remove a cue flag manually, press Ctrl+Q or check/uncheck "Cue" in the part properties dialog (Edit menu).

The Edit button removes the highlighted edit point and restores the original audio at this position. Also a corresponding selection will be created.

If an edit point was created by paste, editing is not possible. In this case the audio data between two parts is not continuous and there is nothing to restore. To remove such insertions, select them and use the function "Remove selected elements" in the Edit menu.

Edit menu: Cut, Copy, Paste

While the Cut button does not copy the cut range to the clipboard, Cut and Copy from the Edit menu do. The copied range can be pasted to any new position (current or selection). Copy and Paste can handle multiple files and parts and work completely non-destructive. This means that no audio data is copied but only access informations.

Level changes

You can create manual fade curves by adding cues and then drag the gray handles with the left mouse button (or Ctrl+Up/Down). To move an edit point, drag it with the right mouse button. For fading in or out you can use the Simple fade or the Two stage fade function in the Edit menu.

Audio ranges with a modified volume are shown in the color of edit points. The gain sign of the edit point shows the level change in dB.

Level change works only on MP3. For AAC and MP2 it is not possible. As the MP3 data remains encoded, the level can only be changed in a resolution of 1.5 dB steps.

The Level... function of the Edit menu is only recommended for special purposes like silencing an area or for setting the "Bottom level" value, which is also used by Simple fade, Two-stage fade and Auto crop. "Bottom level" can also be set in the configuration dialog.

Move and trim edit points

For simply moving a cue or level change point, drag it with the right mouse button (or use Alt+Left/Right for the highlighted point).

You can trim directly the boundaries of an existing cut without converting it to a selection: With the keys Ctrl+1/2/3/4 you can shift audio data on the left or right side of the cut in or out.

Prelisten and save

Prelisten

Before making a cut or an export from a selection, it can be prelistened in order to adjust it (see above). Use the corresponding buttons or the keys F4 to F9 to listen the beginning or end of the selection, play the selection as loop, or as cut. Every cut can be undone individually by highlighting it and choosing Edit (see above).

Save modes

Save complete audio: Saves the complete shown audio data as edited.
Save selection: Exports only the range of the selection.
Save re-encoded: Encodes the complete audio with the current Record encoding settings.
Save split: Creates seperate files for every range between two cues.

You should check the output file(s) before deleting the original(s). Cues are shown as dotted line.

Pause detection

This function sets cues or cuts to gaps of definable length and level. The settings must be adjusted carefully because the results can be very different.

The Level and the Duration sliders adjust at which audio level and gap duration thresholds a pause will be detected. Offset is the number of frames at the pause end which the cue will be shifted to the left or right. Cut whole pause means that not only a cue at the pause end will be created but a cut over the whole pause (beginning of cut slightly right shifted) if the pause is long enough. Don't use the Cut option when you want to create only a Cue sheet!

The value of "After a pause detection skip" can be used to speed up the detection process. If a pause is found, the program jumps further the entered amount of seconds. E.g. if you know that all of the tracks of your CD image are 3 minutes or longer, you could set this value to 150 seconds.

Recording

For recording MP3 directly, you need either an ACM Codec with encoding capability or the free Lame Encoder DLL. It's important to choose a base filename. Your recordings will be saved under this name. Note that there will be no query for overwriting existing files! If you select Add date and time, each recorded file will have a date and time stamp in its filename.

To initialize recording, press the Record button. Then you can see the input level on the meter on the right. After pressing Play the file starts being written. With selected Append data in the recording settings, an existing file will not be deleted and you can make multiple recordings to one file. But take care not to use different bitrates or samplerates in one file. On appending in VBR mode you will only see the time of the current recording in round brackets.

While the recording you can set up to 60 cues by pressing Set begin. The number and position of the last cue is shown in the range field.

The value of Buffer shows how much data is waiting to be encoded by the codec. If it grows, the computer is not fast enough to encode MP3 in realtime. On modern systems it should be always near 0%.

You can limit your recording to an adjustable time. The value can be set in minutes in the Folders tab of the Settings window. The remaining time will be shown below the recording time instead of the buffer. The time limitation value can also be used to record into multiple files. By checking "Continue in new file", the recording will be split into files with a length set by time limit.

If you launch mp3DirectCut with "/rec" in the command line, it will start the recording immediately with the encoding settings of your last session. You can use this option for automated recordings. See more under Command line options.

More features

Fast play can be enabled and adjusted with two prelisten buttons. While playing, they show the symbols >> - and >> +. Also the keys F7 and F8 can be used.

The Margin button shows the room between the highest found level and the maximum of 0 dB since play or record was started. It helps to see how much reserve is left e.g. when recording. The button resets the margin seek.

The Normalize function seeks the whole file (or the selection) for the highest level. If there is room to the maximum of 0 dB, it suggests the corresponding gain. Scanning the file may be slow, because for searching peaks the MP3 must be temporarily decoded. Level adjustment is not possible on AAC or MP2.

Auto cue lets you split the audio into small segments of same length. The function affects either the whole file, if nothing was selected, or just the selection. After setting the cues you can call "Save split..." and choose a destination for writing the file series.

Auto crop removes silences at the beginning and the end of the track automatically. The silence level can be adjusted under Settings > Misc > Bottom level. The accuracy of the function cannot be guaranteed. You should check the result before saving.

Project files and Cue Sheets

An mp3DirectCut project file (*.mpd) contains the complete edit state with every part and their level, cut and cue informations. If you work with large files and make a lot of cuts you should frequently save your work to a project file.

Cue Sheets (*.cue) contain a link to an audio file and time indexes (cues). Cuts and level settings cannot be saved to a Cue sheet. When loading a cue sheet, the program reads titles and artist names and shows them in the graph area and in the Naming dialog. If you split a file by using a Cue sheet, you can create filenames with titles and ID3v1.1 tags for each file.

Keyboard shortcuts (selection)

Page up/downMove back/forward defineable large step (<<< / >>>)
Arrow left/rightMove back/forward defineable small step (<< / >>)
Arrow up/downJump to beginning/end of selection
Ctrl+Left/RightJump to previous/next part
HomeJump to track beginning
EndJump to track end
Shift+Left/RightMove one frame backwards/forward
Shift+Up/DownZoom in/out
SpacePlay/Stop
Ctrl+Up/DownChange gain of current edit point
Delete or CCut
PPlay
SStop
EDelete/edit current point
BSet selection beginning to current position
NSet selection end to current position
RActivate recording (then start with Space)
1...6Selection fine adjustment
Ctrl+1...4Trim current point
Ctrl+5/6
or Alt+Left/Right
Move current point
Ctrl+DToggle play decoder (ACM/mpglib)
Ctrl+JToggle keeping ID3v2 tag
Ctrl+LEnter selection field
Ctrl+PEnter position field
Ctrl+QToggle Cue flag
Ctrl+F4Close file
F4...F9Prelisten
F7, F8While play: Fast Play speed (decrease/increase)
F11Settings
F12Encoding settings
BackspaceMargin reset

More shortcuts are shown in the tooltips and in the menus!

Command line options

Usage:

mp3DirectCut.exe <filename> <option(s)> <destination>

<filename> means every file type known by mp3DirectCut (MP3, MP2, AAC, Project files, Cue sheets).

If you use the <filename> parameter together with /rec you can set an individual record filename that differs from the base filename of the recording settings.

The following options can be used to let the program perform an action immediately. After finnishing, the program quits.

Adjustments for Normalize, Auto cue, Encoder settings and so on cannot be given over the command line. They must be made before in the normal program environment.

Examples:

mp3DirectCut "artist - song.mp3"
mp3DirectCut track01.mp3 /normalize /overwrite
mp3DirectCut audiobook.mp3 /autocue d:\split
mp3DirectCut album.cue /split
mp3DirectCut /rec
mp3DirectCut other_recname.mp3 /rec

Options:

/normalize Normalizes the file up to 0 dB. Higher or lower levels cannot be set by command line.
/autocue Splits the given file into segments of the time set in the Autocue dialog. Also for the Split operation the current settings from normal program usage are applied. <destination> can be an existing folder to save the split files to.
/autocrop Cuts silences from beginning and end of track using the "Bottom level" value.
/split Needs a Cue sheet or Project file and splits the audio file(s). If a <destination> folder is set, the split files will be saved there.
/pausesplit Runs the pause detector and splits the given file at the found pause positions. <destination> can be an existing folder for the result files.
/save Opens and saves the file. Simple re-save can be used for removing incomplete frames or unwanted headers.
/overwrite Replaces the original file. The current "Keep date of source file" setting is applied. If /overwrite is not set, the given file extension will be appended once more.
/rec Starts recording immediately. This can be used e.g. for timed recordings. For multiple automated recordings be sure to check "Add date and time" or "Append data" in the recording settings, otherwise previous recordings will be overwritten. If a filename is given before the /rec option and "Add date and time" or "Append data" is not (!) selected, the program records into a file of that name.
/localini Forces a portable/local settings file in the program folder. Instead of this command line option you can also use the corresponding option in the Folders page of the settings. It creates a tag file with the same effect.

Copyright © 2000-2022 Martin Pesch