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Sample_editor.doc
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Sample editor
=============
OctaMED has a built-in sample editor for sampling and simple editing operations.
The sample editor is activated by clicking the SMPED gadget.
When you load a sample, its waveform is displayed on the sample editor screen.
At the right top corner of the waveform display, there's a number telling
the number of bytes currently displayed. Initially it's the length of the
sample (whole sample displayed).
Below the waveform, there's a red bar. This tells you the size of display
relative to the size of the whole sample, and your current display position
in the sample (this is meaningful when you zoom in).
Buffer size
===========
At the left side of the screen, there's a gadget labeled BUFFSIZE. This is
the size of the current sample (waveform buffer). If you want to increase the
size, you can type in a new value. You'll be asked if you want to clear the
sample, or retain the sample already in memory. Also, if there's no sample in
memory, you can create one by entering a size.
Maximum buffer size is 131072.
Selecting range
===============
Many editing operations work with a specified range. The range is set in the
sample editor by clicking the RMB and dragging. The RNGSTRT/RNGEND show the
actual byte positions of the start and end of the range. You can also change
the start/end positions by entering a new value into them. The RANGE ALL
gadget selects the whole display.
When you've selected the range, you can readjust start/end point by holding
the Shift while dragging with mouse. The other point is the left untouched.
Playing
=======
Next to the BUFFSIZE-gadget, there are gadgets PLAY DISPLAY and PLAY RANGE.
"Play display" plays the current display with the current period value (see
below). Play range plays the selected range. The whole waveform can be played
simply with the keyboard (as usual). There's a red line showing the point
currently being played.
Zooming
=======
For accurate editing, the zoom is very important. There are many ways to zoom
into the waveform.
1. Use the ZOOM IN to zoom in, or ZOOM OUT to zoom out (I wonder if this is
too complex...??? :-)
2. Select a range, then click SHOW RANGE. The range is then displayed on the
screen.
When you want to restore the whole waveform to the view, click SHOW ALL.
These controls should be familiar to AudioMaster users.
When you've zoomed in, it's often necessary to move around the sample.
You can scroll the displayed area with cursor right/left-keys.
Sampling
========
OctaMED has the basic sampling operations built-in. The MONITOR gadget shows
you the real-time waveform input from the sampler (multitasking disabled).
Click mouse button to stop. The RECORD gadget is used for sampling. Click
it, and the real-time waveform appears. Now you can click the left mouse
button to start sampling, and right mouse button to cancel. When you click
the left button, the screen blanks, and sampling starts. The sampling stops
when the waveform buffer is full. You can also interrupt sampling with the
right mouse button.
Sampling/playing rate
=====================
On the right side of the screen, the current sampling/playing period is
displayed (default 428). This is the value that specifies the pitch of the
sound. You can change the period by entering a new value into the PITCH-integer
gadget, and pressing Return. E.g. to double the sampling speed, you could
type in the number 214. You can also change it by clicking on the note,
holding the button and entering a new note using the keyboard.
Changing the sample rate
========================
If you have a sample with period 428 (C-2), and you'd like to transpose it
to play G-2 when you play C-2, then you do the following:
1. Make sure that the current period is 428.
2. Click the note of "Dest"-gadget, hold the button and press G-2 (if octaves
1+2 are used, it'd be T).
3. Click the CHANGE RATE -gadget. Now the sample is transposed (its size will
change).
If you simply want to transpose the sample one octave up/down, there are two
shortcut gadgets for that. Oct (up arrow) transposes the sample 1 octave up,
halving its size, while the Oct (down) transposes it down (doubling the size).
Selecting the save format
=========================
On the bottom right corner, there are gadgets for selecting the save format,
labeled RAW and IFF. These affect the operation of the filerequester option
Save, sample. If raw is selected (default), no IFF chunks will be saved. When
IFF is clicked, the samples will be saved in IFF 8SVX format. The repeat/
repeat length values are then included in the saved sample.
Basic editing operations
========================
The sample editor contains the basic editing operations, that exist in every
sample editor. They're located on the bottom left corner, and they are:
CLR Clears the current range.
DEL Cuts the range (it will not be copied to the copy buffer).
CUT Cuts the range, and puts it to the copy buffer.
COPY Copies the range to the copy buffer.
PASTE Pastes the contents of the copy buffer to the position pointed
by the cursor (range with length of 1 byte).
If you want to get rid of the copy buffer (freeing the memory it takes), click
DEL CB.
Additional operations:
S>CBUFF copies the whole sample to the copy buffer
CBUFF>S copies the copy buffer to the sample
These can be used for implementing a simple "Undo". E.g. if you're
experimenting with echos, you can quickly make a snapshot with S>CBUFF. Then
you can do the echo operation, listen to it, and if you're not satisfied, you
can quickly get back the original with CBUFF>S.
Reversing
=========
You can reverse a range with REV-gadget. The area is then turned backwards.
This is useful if you want to search for hidden messages from a certain kind
of rock-tunes. Anyway, it's fun to record your own voice and then turn it
backwards.
Mixing
======
This mixes two samples together. The source sample must be in the copy buffer.
Then position the cursor (click RMB, but don't drag) to the point where you
want the second sample to start, and click MIX. You can also drag a range and
then click MIX. In this case, only the area selected in range is affected.
Changing volume
===============
This effect allows you to change the volume of the sample, and create fades.
Next to the CHANGE VOLUME -gadget are two integer gadgets. The left is the
start volume, and the right is the end volume. Both are percentages of the
original waveform. First you have to select the range to affect. Then look
at these examples:
1. Double the volume:
set both start and end volume to 200
2. Make the sound fade out:
set start vol to 100 and end vol to 1
3. Make the sound fade in (starting from the half of the final volume)
set start vol to 50 and end vol to 100
After you've entered the start and end volumes, click CHANGE VOL, and the magic
is done. If you increase the volume too much, the normal waveform limits are
exceeded and distortion will occur.
Echo
====
With echo you can do some special tricks to the sound. This feature is learnt
best by experimenting. Some facts should be known though. The echo-feature in
OctaMED's sample editor is controlled with two values: Delay and number of echos.
Delay is the distance (specified in steps of 8 bytes) between two echos. If
it's very low, you can produce some interesting results. Number of echos is
the total number of echos. It should usually be quite low (1 - 10), but you
can experiment with higher values.
Usually you have to extend the workspace by inserting blank space for the
echos after the end of the sample. This is can be easily done this way:
1. Click S>CBUFF.
2. Enter the number of inserted bytes in BUFFSIZE gadget.
3. Be sure that the cursor is in the beginning of the sample and click PASTE.
Now, start playing. Activate DLAY-gadget, enter value, hit Return, enter
the number of echos. Finally click ECHO, and listen...
Filter
======
This is a simple-to-use feature that allows you to smooth sample (reduces
noise). Select the range to filter, and click Filter.
Boost
=====
This is the exact opposite of the Filter, and it works in the same way. It
makes the affected area sound brighter. The noise becomes more audible, too.
Setting loop points
===================
OctaMED has two blue loop markers for selecting the range of looping. Click
'Loop on' to turn on looping. Click again to turn it off. When the looping
is on, you can change the loop point by dragging the markers with the mouse.
Some gadgets help you to find good loop points:
S select start marker
E select end marker
< move start/end marker 2 bytes left
> move start/end marker 2 bytes right
<0 move start/end marker left until a zero is found
0> move start/end marker right until a zero is found
The S and E gadgets select, if the <, >, <0 and 0> gadgets affect the starting
or ending point. The ZOOM IN/OUT gadgets are useful for finding the range, as
they allow you to examine the waveform very accurately.
Creating noise
==============
This quite unusual feature allows you to add noise to your samples!!
Select a range, enter the noise level (1 - 127) to the integer gadget next to
it, and click 'Noise'. At first it may seem useless, but in fact it isn't!
First, you can easily make wind/sea effects etc.. Then, the noise generator
can be a source for more complex instruments, when used together with filter,
boost, echo etc.. It's possible to create excellent instruments even without
a sampler (believe me!).
R>SY
====
This gadget allows you to transfer the selected range to the synthsound editor.
The range should be 2 - 128 bytes long.