mp3DirectCut
User Manual
Table of contents
What is mp3DirectCut?
mp3DirectCut is a frame based editor for MPEG audio.
You can set regions for cutting or changing the volome
like in common audio editors. At all operations the file
will not be re-encoded. This saves time and disk space
and prevents loss of audio quality. You can easily
navigate through even large files and mp3DirectCut
gives you a visualisation of the MP3 audio data.
Basic Settings
The program needs either an installed MP3 ACM Codec
or the 'mpglib.dll' to decode MP3 for playback. The
mpglib.dll with the complete source is available at
mp3DirectCut's
homepage.
It is based on the mpglib which is originally
provided by Michael Hipp (www.mpg123.de).
Since version 0.92 mpglib.dll decodes Layers 2 and 3.
Which decoder fits best depends on your machine. The
mpglib.dll makes the editor independent (if you don't have an
ACM) and supports Layer 2. But it takes more cpu than ACM.
You can adjust the amount of frames decoded to each play
buffer between 'fast' (1) and 'reliable' (8). On slower machines
set a higher value. If you want to have a fast response of
the graphics select a faster value.
Navigation
As mp3DirectCut is designed to handle large files,
there are many ways to reach a position:
Scrollbar
[<<<] [<<] [>>] [>>>]
Mouse
[I...<<] [>>...I]
Edit Menu and [I<] [>I]
Some words about visualisation of MP3: the audio graph
takes volume information directly from the MP3 frames and
differsfrom the real decoded audio amplitude. Even the
height which the frame bars can reach varies by different
MP3 types. The graph is for orientation and searching
positions. For a more reliable audio level use the
VU meter on the right.
Some words about visualisation of MP2: it's of pure
statistical style and contains no audio information.
Audio editing
1. To edit a part of your track you must first make or
change a Selection using one of these ways:
The arrow buttons move a sinlge frameback or forward,
the page up/down areas skip the file by +/- 100 MPEG frames (2-3 seconds).
You can even use Keys to control the Scrollbar (Arrow l/r and Page u/d).
But this is only possible with a focused scrollbar. For quickly focusing it
you can press TAB.
These buttons are user definable.
You can set the amount of frames to skip back/forward
in the configuration window between 10 and 10.000 for
[<<<] and [>>>] and between 1 and 1.000 for [<<] [>>].
You can directly jump to any file position by
left clicking into the map area below the audio graph.
And: holding down the CTRL key and clicking into the
audio graph jumps to the shown audio position. Moving
the mouse slowly with button pressed allows smooth scrolling.
These buttons will set the position
to the selection's beginning or end. If there is no selection
the position will set to the active region (cut, gain, cue).
Let you choose the active region and sets the position to it's beginning.
[Set begin] [Set end]
These buttons will set the beginning or the end of the
selection to the current position.
Mouse
You can choose between two selection method in the Settings:
2. With your selection you can set one of three types of regions:
Cuts and Cues
To make a normal cut mark a
selection and press [Cut]. If the selection has a length
of 0 it will become a cue. Cues do not modify the audio,
they can be used to locate positions and must be used
for creating a cue sheet (see under Project files).
While recording a cue can be set by pressing [Set begin].
Cuts do not disappear like in common audio editors. You will see them with a different background color.
Gain regions
The [ Gain ] button opens a dialog which lets you modify
the volume of the selection. 'from .. dB' sets the initial volume
change, 'to .. dB' the final. So the range can be faded in any
direction orconstantly changed. All volume changes are made in
steps of 1.5 dB and nothing will be re-encoded.
Volume regions are shown with the same background color but different color of audio data. Note: Volume change works only with Layer 3.
A gain region can also be created using the Normalize function in the edit menu. It scans the selection for the loudest amplitude and recommends a value to raise the volume to reach the maximum of 0 dB. This value can be adjusted with the slider. Going over 0 dB may cause distortions.
3. Change or remove existing regions
First set it the "active region" (highlighted). The easist way to do so is by using the "Autoselect" option (enabled by default). Alternatively you can highlight the regions as described in the Navigation section. Second press [Edit]. The region will become the selection and will be deleted (!). So after changing boundaries you must hit [Cut] or [Gain] again. Previous gain settings will be kept.
Limitations
The maximum number of different edit regions is 200.
Cuts and gain regions cannot overlap each others. If you
cut a selection which covers other cuts they will all
be merged (be careful with gains, they will also be
converted!). If you set a new gain which covers other cuts
nothing will be merged but the gain region will be shortened.
Prelisten and output
Normal play ist already a prelisten mode because every cut and every gain modification is played as it will be saved. In addition there are two buttons to prelisten the selection before cutting:
[...=>II=>...] plays some seconds before and some seconds after the selection and then returns to the last cursor position. [I=> ... =>I] plays the beginning and the end of the selection.
A created file can either be the whole data outside the cuts ('Save...') or you can save only the selection ('Save selection...'). You can also save multiple pieces at once: 'Split file...' creates seperate files for every region between cuts or cues. Note: You should ALWAYS CHECK the output file(s) before deleting the original.
For compiling files in any arrangement use 'Append selection...'. Your selection will be appended to the choosen file. But take care not to combine different formats. Type, mpeg version, layer, bitrate, samplerate... must fit. The program will NOT check this.
Recording
For recording an MP3 directly to disk you need either an ACM Codec or the Lame Encoder DLL (available through the homepage of the Lame project: www.sulaco.org/mp3). It is 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 & time' each recorded file has date and time in its filename.
To initialize recording press [Rec]. Then you can adjust the audio level using the VU meter. 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.
While recording you can set up to 40 cues by pressing [Set begin]. The number and position of the last cue is shown in the range area.
The value of 'Buffer' shows how much data is waiting to be encoded by the codec. If it grows the codec is not fast enough to encode MP3 in realtime. Take care that the used buffer size is not over 10% for more than some seconds.
If you launch mp3DirectCut with '/r' in the command line it will start the recording immediately. You can use this option for automated recording. See more under Command line options.
Project files and Cue Sheets
An mp3DirectCut project file (*.mpd) contains the name of the audio file and all cuts, gain regions and cues. 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 only the audio file and cues (cuts with a length of 0). Cuts and gain settings will not be saved. When loadind a Cue sheet the program reads title and artist names and shows them in the graph area. If you split a file using a Cue sheet you can create filenames with titles.
Command line parameters
Files and Projects
Every file type known by mp3DirectCut (MP3, MP2, project
files, cue sheets) can be loaded via the command line or
Drag&Drop. If you add mp3DirectCut to these file types
you can open them directly from the Explorer.
Auto record
'/r' starts the recording immediately. Use this feature for timer
recordings. With Window's scheduler you can also set a duration
time after which the program will be terminated. For multiple
timer recordings be sure to check 'Add date and time' or
'Append data' in the recording settings, otherwise previous
recordings will be overwritten.