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Text File | 1991-06-23 | 17.0 KB | 464 lines

Help for !DSEdit v1.03 by Jason Williams ======================================== **************************************************** * * * This version of !DSEdit is PUBLIC DOMAIN * * © Copyright '89,'90,'91 Jason Williams * * * **************************************************** DSEdit is a raw-digitised-sound editor. It can be used to edit/play samples from the Armadillo range of sound samplers as well as EMR's SoundSynth samples (Note that loading a soundsynth sample converts it to DSEdit raw sample format, so it will no longer be compatible with soundsynth unless loaded as a raw sample). Up to 16 samples can be edited at one time. To load a sample, double-click the sample's file icon in a directory viewer, or drag the icon to the DSEdit iconbar icon. A window will appear containing a graphical representation of the sample, and some other icons. The main sample display. This shows the sample. Initially it is all inverted, indicating that the entire sample is selected. You can select any small portion of the sample by dragging across the display. The selected portion is acted on by most of the editing options, so it is important to select the area you are interested in before you use editing options. (Note that dragging with the Select button will select a new area of the sample, while dragging with the Adjust button will adjust one end of the selected area) [To vaguely explain the picture of the sample: A DSEdit raw sample is a sequence of bytes representing sampled values. These are actually 'amplitude' or 'speaker deflection' values for playback. A typical sound sample will be at 22kHz, which means that 22,000 bytes are 'played' through the speaker every second. The value of each byte is in the range 0 to 255, whith a value of 128 meaning silence (no speaker deflection), and values 0..127 represent negative deflection (volume/amplitude) and values 129..255 representing positive deflection (volume/amplitude). The displayed picture shows the values of bytes across the entire sample- silence would be a line across the centre of the display. The higher the 'peaks' on this display, the louder the sound is when played. If any bytes of the sound (through amplification, for example) go outside the range 0..255 (i.e. move off the top or bottom of the picture) distortion and static-like sounds may result.] The purpose and usage of the icons across the top of the editor window is as follows (from left to right): * Left arrow This allows you to scroll the display 1/4 of a screenful to the left (When you have zoomed in on the sample, see below) * Speaker This will play the selected portion of the sound sample at the current speed and volume settings. * Zoom Clicking Select on this button increases the zoom factor. Clicking Adjust decreases it. The icon changes to display the number of bytes displayed within the area shown in the window. Once you have zoomed in, you can scroll the displayed area using the left and right arrow icons. * Right Arrow To scroll right. * Selection display This text line shows how many bytes of the file are in the current selection. (e.g. "Selection 6420 of 32984 bytes") * Speed keyboard This 'piano keyboard' display allows you to alter the speed at which the sample is played. This has the effect of changing the pitch of the sound. Clicking near the left end will give a very low note, while towards the right the note becomes higher. Marked in red on this display are the approximate positions that give playback speeds of 7, 12.5, and 22kHz, the most common sample speeds. Clicking on the keyboard will alter the playback speed, and then play back the entire sample at the new speed. When clicked, this changes the speed, and then plays back the selected area of the sample. Clicking Menu anywhere inside a DSEdit editor window will bring up the main menu with the following options: Play Sound ========== This plays the entire sound at the current speed and volume. Try Sound ========= This is for people like me who like to have a quick and simple way of trying out new sounds- it amplifies the sound as much as possible without corrupting it, and then plays it. Save ⇨ ====== Following the arrow on this option leads to a standard Save box. This will save the entire sample. Select all ========== This selects the entire sound. Selection ⇨ =========== This leads to a submenu which allows you to: * Save the selected area only. * Play the selected area only. * Delete the selected area. Edit ⇨ ====== This gives the main suite of editing functions. Four of the functions are currently greyed-out, as although they exist within DSEdit, the interface has not yet been connected up to them! * Ramp Up will modify the amplitude (volume) of the sample across the area that is selected. This alters the volume from left to right across the selected area from 0 to full volume, acheiving a 'fade in' effect. * Ramp down is the opposite of Ramp Up. It causes a 'Fade out' effect. * Amplify ⇨ Leads to a writeable menu. Type in the percentage by which you wish to amplify the sample. Examples: 50 (50%) will halve the volume, making the sound quieter. 100 (100%) will leave the volume exactly as it is! 200 (200%) will double the volume, making the sound much louder. Note that if over-amplification occurs (When bytes start to 'wrap' or have to be clipped, i.e. the values are amplified outside the range 0..255), distortion and crackle may result. The only way to avoid this is to amplify by a smaller value, or to amplify quieter parts of the sound independantly of louder parts. * Max Amplify is very similar to Amplify, but DSEdit works out the best value to amplify by to get the maximum possible amplification before the sound is corrupted. (essentially, it expands the sound's byte values to fill the full 0..255 range, thus maximising the amplitude) * Move Centre ⇨ Leads to a writeable menu. Type in the new byte-value for the 'centre' of the sound (the "silence" level). The selected area of the sample will be moved 'up' or 'down' (by adding a constant) to shift the byte-value entered up/down to 128 (normal silence value).This is very similar to the 'Add Const' option, i.e. a value of 160 in this option is identical to a value of (128-160=) -32. This is used to correct badly-sampled sounds. * Auto Centre is similar to move centre, above, but DSEdit moves the centre of the sound to the centre byte value in the range used by the sound (i.e. it finds the range of values used by the sound, and places the centre half-way between the minimum and maximum values). This is a quick-and easy way of moving the centre close to where it should be. * Limit up ⇨ * Limit down ⇨ These options are very similar. Enter a byte-value limit into the writeable menu. Any values in the selected area of the sound that are greater than (for limit up) or smaller than (for limit down) this value will be truncated to this value. This can be used to add an unclear-static-y effect (if you want one!), but can also sometimes be used to 'tidy away' spurious (noise) values when these functions are applied to very small selected regions (Use the zoom). * Squeeze ⇨ This allows you to alter the size/length/playback time of the sample. Enter a percentage between 1% and 999% in the writeable menu box. A value of 1%-99% will decrease the length (in bytes, and hence the playback time, and cause the frequency to rise), e.g. A value of 50% will halve the sample size (e.g. 24kB sample will become 12kB), and double the frequency (pitch). The sample should now be played at half the sample-rate (i.e. a 22kHz sample now should be played at 12kHz). A value of 100% has no effect. Values greater than 100% will increase the length of the sample, hence increasing the playback time and decreasing the frequency (pitch). Play the sample at a higher playback-rate to correct the pitch. Note that this option could easily cause DSEdit to crash, as it increases the sample size (e.g. 200% DOUBLES the sample size) Both these options take a while (They process about 1kB every second). Note also that the quality of a sample that has been processed in this way will be adversely affected. Note also that performing squeeze twice with values of (for example) 50% and 200% will return the sound to it's original length and speed, but will DEGRADE the quality of the sample considerably (As half the original information is completely lost) * Make silence ⇨ leads to a writeable menu. Enter the number of bytes worth of silence you wish to insert at this point in the sample. Look at the main window display of the sound length as a guide to how many bytes will be needed to get the right length of play-time inserted. Special FX ⇨ ============ This submenu offers the special effect and conversion options. They are: * Add const ⇨ Adds a constant value to each byte of sound data in the selected region. See later ("Clipping" option) for further information relating to this option. Enter the constant value (0..255) in the writeable menu. Remember that adding too large a number may 'shift' the sample up or down so that clipping/wrapping occurs, which will degrade the playback quality. * Eor const ⇨ Exclusive-Ors a constant value with each byte of sound data in the selected region. This is most useful for converting some sounds (e.g. Amiga formats), by EORing with a value of 128. Enter a value (0..255) in the writeable menu. * Reverse will reverse the selected region of the sample. This results in it playing backwards. * Echo ⇨ adds an echo to the sample. Enter the delay (in bytes) at which each echo occurs into the writeable menu. * Flange Echo ⇨ adds a Flange Echo to the sample. Enter the delay (in bytes) at which each echo occurs into the writeable menu. Options ⇨ ========= This submenu offers four extra 'preference' options: * Set speed ⇨ Enter a byte value for playback speed into the writeable menu. This has been superceded by the keyboard in the editor window, though it can still be used to set the speed. The speed displayed on this menu is also altered by clicking on the keyboard. * Set volume ⇨ This sets the volume at which the sample is played. Enter a number between 0 (quiet) and 15 (loud) into the writeable menu. * Clipping. This option controls what happens to the bytes of sound data when they are modified (By Add const, Eor const, Amplify, merging sounds, etc.) When clipping is ticked, then any values that become larger than 255 are 'clipped' to a value of 255, and any going below zero become zero. With clipping off, values 'wrap' around (MOD 256), so a value of 256 will become 0, 257 will become 2, ... -1 will become 255, -2 will become 254,... and so on. * Lines alters the way in which samples are displayed in the main window- With lines ticked, lines are drawn between values, with it off, dots are placed at each value. Experiment and see. * Filetype. This tells DSEdit to set the filetype of any file you load to 'RawSound' (&ED0). It is very useful for setting the filetype of downloaded files (which normally appear as 'data' files) when loading them into DSEdit for the first time. However, most of the time you are unlikely to want this turned on, as DSEdit will do this to ANY file that you attempt to load, as it has no way of knowing whether the file really is/isn't a sample! These options are not saved and will be reset each time you run !DSEdit. Convert ⇨ ========= This submenu offers options for converting foreign file formats (From Macintosh, Atari ST, and Amiga computers generally, but also from other Arc sound programs) * Logarithmic This converts logarithmic sounds to DSEdit's RAW format. Many relocatable-module sounds on the Arc are stored in this format. * Bit signed This converts 'Bit signed' sounds to DSEdit's RAW format. If a sound doesn't work, then try this one on it! * Amiga This converts "Amiga" format sounds by EORing each byte with 128 (inverts the sign bit). ** This will also work with Soundsynth and ** ** Amiga SoundTracker files. ** * Sun This converts a SUN SparcStation format sound. Extra functions =============== DSEdit has several other extra functions that aren't immediately obvious: Merging sounds: =============== To merge two sounds together, load the first sound into DSEdit, then drag the file icon of the second sound into the edit window of the first sound. A dialogue window will appear with the following options: * Insert at selection start This will load the second sample, and insert it into the first sample at the point where the selected area STARTS (i.e. the LEFT end of the inverted area). It inserts the ENTIRE sample, and does not take any notice of the end of the selected area. * Overwrite from sel. start This loads the second sample, and *overwrites* the first sample, starting from the start of the selected area. NOTE that this carries on until the second sample runs out, and is not limited in any way by the length of the selected area. * Add sounds together This takes each byte in turn from both samples and mixes them by ADDing the two bytes. (Clipping/wrapping occurs depending on whether the "clipping" option is ticked in the Options submenu). This usually results in a louder sound, and can result in distortion. In such cases, either quieten one or both sounds before addition (using amplify of 0 to 99%), or by using the Average option (see below). Note that this only affects the sample in the selected area, adding in the second sound from the start of the selected area until the end of the selected area is reached, EVEN if the second sample is longer than that. * Average sounds together This is the same as Add, above, except the bytes are averaged instead of added. This stops the sound having to be clipped (as happens in Adding), which improves the end-product quality. This results in a quieter sound. Click on the radio-button of the method of your choice, and then click "OK", or click "CANCEL" to abort the merge. Keyboard shortcuts ================== After you have clicked in any editor window, it's title-bar will turn cream (it becomes the input focus). Now, you can use the following keys to duplicate some of the menu functions: SPACE will play the selection RETURN will play the entire sound DELETE or ⇦ will delete the selected part of the sound Page up will increase the volume of the sound (=Amplify by 150%) Page down will decrease the volume (=Amplify by 75%) Copy will select the entire sound ------------------------------------------------------ Please note: This program is not guaranteed to work as expected. In fact, I can practically guarantee that it will crash (locking up the computer entirely) at some time! Usually, this only happens when insufficient memory is available in the RMA for an operation to be carried out, so I suggest you check the free memory before trying to load big sound files! This tends to happen when "Squeeze"ing a sound by values larger than 100%, when the size of the sample increases quite considerably. I accept no responsibility for any loss or annoyment caused by any crash or inadequacy of DSEdit. Note also that because sounds are loaded into the RMA area, if you run any applications or load any modules while any sounds are loaded, the RMA space left when the sound windows are closed may not be recoverable... in other words, your RMA will gradually fill with empty bits of memory that can't be reclaimed! This will eventually cause the system to grind to a halt. The only way to fix this at present is to CTRL-Break (Reset the system), so I advise that to prevent this becoming necessary, you only run other apps when there are no sound windows open. And now for something completely different... ============================================= If you have any suggestions, bug reports (accepted by the dozen only, due to high infestation levels!), or whatevers, or would like a copy of the latest version of anything I have written, or would like to donate a sound sampler board, hard drive, or lots of money towards the further development of DSEdit, then you can contact me at: Jason Williams, | or by email: R.D.2, Manuel Road, | Silverdale, | jwil1@cs.aukuni.ac.nz North Auckland, | NEW ZEALAND. | "Now go away, or I shall taunt you a second time!" -Quest for the Holy Grail