Contents
Introduction
System Requirements
Installation
Brief Guide
The Overall Process
Image And Music Windows
Scanning
Scanner settings
Loading and editing an image
Reading an image
Editing Music
Saving Music Files
Multi-page scores
The Music Editor
What it does and doesn't do
Warnings about rhythm problems
Selections
Deleting symbols
Modifying symbols
Moving symbols
Creating symbols
Joining staves
Irregular systems
Guidelines
Keyboard shortcuts
Problems and Tips
Introduction
Limitations on notation recognised
Image quality
Tips and techniques
Gray notes won't go
Introduction
SharpEye is a music OCR program. It converts scanned images of printed music into Rhapsody 4 files, PMS files, and MIDI files. This is a difficult task for a computer program to perform, and inevitably there will be some errors when the music is complex or crowded, or the input image is of poor quality. SharpEye has a built in music notation editor which has been specially designed for checking and correcting the output before saving it.
System Requirements
You need a computer with RISC OS 3.5 or later. SharpEye uses a fair of memory and processor time. It is likely to be inconvenient or impossible to process many images with 8Mb of RAM, and 16Mb is recommended. Very large scores (eg orchestral scores) may require more than 16Mb. A StrongARM or XScale processor is highly recommended.
You will need TWAIN installed in order to scan using SharpEye.
Installation
SharpEye is supplied on a single floppy disc. To install it on your hard disc, drag the !SharpEye application directory to the desired place on your hard disc. SharpEye is run in the usual way, by double clicking on the !SharpEye icon.
Brief guide
If you don't like reading manuals, and prefer to learn by trial and error, here is a brief guide to get you started.
Scanning
Scan at 300 dpi for most music. A higher resolution may be better if the music is printed small. The scan should be black and white.
Try to make the scan as straight as possible.
Start the conversion by choosing Read... from the image window menu.
The Music Editor
The Adjust button is devoted to inserting new symbols. Use Control-Select for multiple selections.
You'll often have to insert a symbol which is not quite what you want and then select and modify it.
The black rectangles at the start of the score are for joining staves. You should normally join staves that belong to one instrument (usually a keyboard instrument).
Warnings about bars (measures) that SharpEye doesn't understand are shown at the end of each measure, and individual notes that are not understood are shown in gray.
Support and Upgrades
If you have problems using SharpEye, please read this manual first, especially the 'Problems and Tips' section. The most common problems are to do with getting a good quality scan of the music, and if you are new to scanning, this can take some experimenting. Upgrades and any new information about SharpEye will be available from the web site below, so you may find a solution there. If this doesn't solve your problem, or you think you have found a bug in SharpEye, please get in touch via the contact details below.
Address: Richard Hallas, 31 Skelton Crescent, Crosland Moor, Huddersfield, West Yorkshire, HD4 5PN, UK
Website: http://www.hallas.net/
Email: Richard@Hallas.net
The web site for the Windows version of SharpEye is http://www.visiv.co.uk/.
The Overall Process
Image And Music Windows
There are two important windows in SharpEye, one that displays the input image and one which displays the music output.
The Image window displays the scanned image. You can drag sprite files in here. You can open it by clicking Select on the icon bar.
Here is the music output window. You can open it by clicking Adjust on the icon bar.
Scanning
You can scan via the TWAIN interface using Select... and Acquire... from the Image window menu. For this to work you must have a copy of !Twain on your computer and it must have been 'seen' by the computer.
Select... allows you to choose which TWAIN device to use. Normally this only needs to be done once, the first time you use TWAIN. Acquire... will open the TWAIN interface, and allow you to set the area, resolution, etc. For more details see the TWAIN documentation.
Make the scan as straight as possible. SharpEye automatically copes with small amounts of skew, but accuracy is highest when the scan is straight. Be sure that the printed music is flat on the scanning surface. If the paper is not flat, it's likely that the image will be distorted or blurry and this will confuse SharpEye.
Scanner settings
Colours
You should set the colours to black and white. Different scanner drivers use different terms for a black and white image. It may be described as "Monochrome" or "Line art" or "Bi-level" or "One bit per pixel (1 bpp)", or there may be an "OCR" setting which is suitable.
Resolution
You should set the resolution to 300 dpi for most printed music. A higher resolution (eg 400 dpi) may be useful if the music is printed small or a lower resolution (eg 200 dpi) if it is large.
As a check to see if you've got things right, an uncompressed black and white scan of an A4 page at 300 dpi will be about 1Mb in size.
Brightness
The default brightness level is usually fine. One thing to watch is that with high quality printing, the staff lines may be very thin (less than 1/300 inch) and may become broken when scanned. In this case reducing the brightness may improve things a lot. With poorer quality printing the lines are usually thicker, or already broken, and the default brightness level is usually best.
Miscellaneous
Some scanners have settings such as 'photo', 'halftone' or 'dithered'. These attempt to represent grey levels with patterns of black dots and are not helpful for OCR (music or text), so turn these settings off. Options such as 'text' or 'line-art' are probably a good thing.
See the section on image quality to get an idea of what kind of scans SharpEye can cope with.
Loading and Editing an Image
To load a sprite into SharpEye, drag the file into the image window or to the icon bar.
You can zoom the view of the image to different sizes using Zoom from the Image Menu. This doesn't change the image, just the way it looks on screen.
You can invert the image if necessary (swap black and white) using Invert from the Image menu.
You can also rotate the image by multiples of 90 degrees using Rotate from the Image menu.
Reading the image
To convert the image, choose Read... from the Image Menu. You will be asked if you want to save the image if you have not already done so. You should normally save the image so that SharpEye can load it again when you are editing the music.
Choosing Read... starts another program (the "music OCR engine") which does the conversion. A small progress window will open while this is happening. This can take some time, depending on the size of the image and the complexity of the music - and the speed of your computer of course. Once the engine has finished, the result will be loaded into the music editor for you to check and edit.
You can stop the reading process once it has started by clicking the Stop button in the progress window.
If the recognition is poor, please see the section above titled 'Scanner settings' and the one titled 'Image quality' in the 'Problems and Tips' chapter.
Zones
If you want to process only part of the image you can create a zone around the area. You can use the mouse to drag out a rectangle in the image window. This can then be adjusted using the eight handles around its border, or moved as a whole by picking it up in the middle. You can delete it from the Image Menu or using the Delete key.
Multitasking rate
The engine uses 'idle' time to process the image in the background, while you can do other things with the computer. You can decide how much time the engine uses by setting the rate via Choices... in the icon bar menu. A lower value makes the computer more responsive, a higher value makes the processing go faster. The value is the number of centiseconds the engines uses before letting other applications have a go.
Normally you should not have to change this from its default value, but unfortunately some programs claim idle time when they don't need it, and this can make the engine very slow. Increasing the value can help with this. Be wary of using a very high value (above 100 or so) as the computer will become difficult to use until the engine is done.
What the engine does
You don't need to know what the engine is doing, but you may find it interesting. It goes through the following stages:
Starting - Loads data files and the image.
Finding edges - Traces around the shapes to model them as polygons.
Finding skew angle - Finds the skew of the image to correct for it (up to 2 degrees or so).
Finding staves - Finds the scale of the staves and locates them.
Reading text - Uses traditional text OCR to read lyrics etc.
Finding note heads - Searches along staves and ledger lines for notes.
Finding beams - Locates shapes that may be beams.
Finding verticals - Locates shapes that may be stems or bar lines.
Finding slurs - Locates shapes that may be slurs and ties.
Consistency checking - Checks the shapes found so far for consistency with one another.
Erasing objects - Removes the shapes found so far from the image
Finding symbols - Locates all the fixed size symbols: clefs, rests, flags, etc.
Analysing - More consistency checks, and joining everything together.
Editing Music
Most of the time you are using SharpEye, you will be checking and correcting the output in the music notation editor. The next chapter is devoted to this.
Saving Music Files
Use Save from the Music editor's menu to save the music. You can save the music as a Rhapsody4 file, a MIDI file, a PMS file, or in SharpEye's own format. If you save it in its own format, you can load it back later and continue editing. SharpEye does not load Rhapsody4, MIDI or PMS files.
You can choose how much correcting to do in SharpEye, and how much to do elsewhere. For example, I find it easier to correct lyrics in SharpEye than Rhapsody 4, but easier to correct lyrics in PMS than SharpEye.
There are a few options for output available from Choices... on the icon bar menu. MIDI output is also affected by the settings at the start of the score (the black circles and rectangles).
MIDI Options
You can set the tempo for the piece. This value is in crotchets (quarter notes) per minute, regardless of the time signature.
You can decide whether repeats signs taken account of or ignored when generating the MIDI file.
You can choose whether to include any lyrics that SharpEye has found.
You can make SharpEye put different voices on different channels, so that notes with up stems will get a different channel number to those with down stems. This can be set per stave using the circles at the start of the score. You can toggle between one circle (one channel output for that stave) or two by clicking on them.
You can join pairs of staves. This puts both staves on one MIDI channel. This also changes the way that SharpEye analyses the rhythm, and is described in more detail in the section "Joining staves".
Rhapsody 4 Options
You can choose whether to include any lyrics that SharpEye has found.
You can choose whether to remove unnecessary clefs and key signatures at the starts of systems. SharpEye generates a Rhapsody 4 file with a single system, so it only requires clefs and key signatures at the start, and when they change. You might want to leave the clefs and key signatures in if you are doing much correcting in Rhapsody 4, since they do make it easier to relate what you see in Rhapsody 4 with the original.
Limitations
There are some limitations on what information SharpEye outputs.
For the MIDI output, this is mainly due to the limitations of the MIDI format. Among other things, there is no provision in MIDI for stem direction, beaming, slurs, or more than one line of lyrics. Even bar lines and clefs cannot be put into a MIDI file, although the program that imports the MIDI file can usually reconstruct these. You may also find that not all the information that SharpEye outputs is understood by the importing program. For example, some programs ignore lyrics.
For Rhapsody 4 format, SharpEye outputs ties, but not slurs or phrase marks. (This may be remedied in a later version.) It does not put the original beaming into the Rhapsody 4 file because Rhapsody 4 has its own algorithms for deciding beaming and it would be confusing if SharpEye tried to override this. SharpEye does not try to mimic the original layout of the music in Rhapsody 4.
For PMS format, SharpEye outputs lyrics a bar at a time, but you will sometimes find that syllables appear under the wrong notes, and you will have to insert hyphens and/or equals signs. Sometimes, PMS will give an error about 'a slur of zero length'. This is usually due to a note which has one slur ending at it, and another beginning at it.
Multi-page scores
Music scores are often more than one page. You can deal with these in several ways.
You can convert the pages individually into MIDI or Rhapsody 4 format, and join them together in a MIDI editor or Rhapsody 4.
Alternatively, you can convert the pages individually into SharpEye's own format and then join them in SharpEye. After conversion, load the first page into the music editor, and add the rest in the right order to join them, by dragging the files in. You will be asked if you want to replace the existing score or join the new one onto the end, so choose Append to join the pages. You can do corrections before and after joining. If you do the corrections separately, you will usually have to add a time signature to the start of the second and later pages. If you have joined pages, SharpEye will automatically load the correct image as you edit different pages, as long as the image files are still where they were when first processed.
Note that there is currently no way to undo an append operation, so it is best to save your work before adding another page to it. This is particularly important if you have several pages joined together and have spent a lot of time correcting them. Make sure you save this before adding another page which might be from a bad scan or even the wrong page.
The Music editor
What it does and doesn't do
The music editor in SharpEye 1.0 never formats the music. For this reason alone it is not suitable as a general purpose music notation editor. It is designed only for correcting the output from the music OCR process.
On the other hand, it has several features that are designed to help with the corrections.
The music editor window is linked to the image window, so that when you click in the editor, the image scrolls to the same place in the image.
It displays warning symbols at the end of each bar (measure) that has errors or ambiguities in the rhythm. It also draws any note heads that it can't understand in grey. This works a bit like a spell checker, and directs your attention to likely errors.
It is intended to be easy to learn. Almost everything can be done with the mouse and the Delete key. Note that SharpEye uses the Adjust button for inserting symbols, and Control-Select for multiple selections.
SharpEye does not try to ensure that what you do looks good. There are many ways of writing a piece of music which will produce the same sound (and in most cases the same MIDI file). Some are sensible and some aren't - SharpEye doesn't try to make you sensible! SharpEye is also fairly limited in its ability to avoid clashes of symbols, and in complex or crowded music symbols may overlap one another.
Warnings about rhythm problems
SharpEye uses two methods to indicate problems with rhythm. At the end of each measure that contains a problem, just below the bar line, it displays a warning symbol (a blue triangle). In such a measure, it may also display some of the notes in gray instead of black. This means SharpEye is not sure when they should be sounded. SharpEye also displays ties, slurs and lyrics in gray if it doesn't know which notes to attach them to.
If you see the warning sign, but no gray notes, it means there are not enough notes or rests to fill the measure. This is probably because SharpEye has missed a note or has made a note too short, perhaps by missing a rhythm dot. If there are warnings on lots of measures, it may be a time signature error. If SharpEye misses, or misreads a time signature, or if the music is from the middle of a piece and so contains no time signature, it will cause lots of warnings.
If there are gray notes, there are two main causes. The first is the opposite of the problem above: SharpEye has 'seen' a note (or rest) that is isn't really there, or made a note too long by missing flags or beams, or there is a time signature error.
The second cause of gray notes is a bit more subtle. It may be that there are neither too few nor too many notes, but it is still not clear when they should sound. This typically happens in keyboard music, where two staves are used for one instrument. By default SharpEye looks at each stave individually when analysing measures. But keyboard music often only makes sense by looking at both together. The best cure here is to join the two staves at the beginning of the score. An alternative is to add rests to fill in the gaps in each stave, but that's usually a lot more work!
Selections
You can select objects by clicking on them, and they will become red. Once they are selected you can modify them or delete them.
Clicking on a bar line or time signature will select all the ones vertically above and below in the same system (ie all the ones that occur at the same time).
When you click on a note head that is part of a chord, it will become red and the rest of the chord will become dark red. This is to indicate that you can modify either the chord or the single note but pressing Delete will just delete the note. You can select the whole chord by double-clicking.
You can select multiple notes and chords by using Control-Select, as long as they are all in the same system.
You can select a complete line of text by double-clicking on it. It can then be deleted but not otherwise modified.
When you have selected something, you can delete it with the Delete key. Also a tool pane with dark red symbols will open at the top for modifying the selection.
Deleting objects
Symbols are deleted by selecting them and using the Delete key.
Note that some objects - rhythm dots, triplets, accidentals, and articulation marks such as staccato, tenuto, accent and the pause sign (fermata) are regarded as properties of notes and not as symbols in their own right. In order to 'delete' these, you should select the note or chord they belong to and modify it appropriately.
If you select a lyric word, the delete key operates in the editable field in the tool pane, ie deleting individual letters. If you select a whole line of text (by double-clicking) you can delete it with the delete key.
You cannot delete the rightmost bar line in a system.
Modifying Symbols
The general method is to select the object(s) you want to change in the score, then click on the symbol in the tool pane that you want to change it into.
Keys and clefs
These are straightforward, the only slight complication is when a key signature changes the key to C. The natural sign in the key signature tool pane is for this. If you change an existing key signature using this, it will show as the right number of natural signs to cancel the last key signature.
Time Signatures
If you can see the symbol you want, click on it as with clefs and keys. For less common time signatures, enter the signature in the writable icon (eg "12/16") and then click on the p/q symbol next to it.
Lyrics
You can edit lyrics a word (or syllable) at a time in the writable icon. A common error in the conversion is that SharpEye runs two syllables together when they are closely spaced: these can be easily corrected. If you insert a space in the word, SharpEye will split the word into two at this point. It attempts to attach the parts to nearby chords. If this fails, one or both parts will become grey, and you will need to move them.
Rests
You can change the kind of rest and also set the number of rhythm dots. To remove any rhythm dots, click on the empty circle. (This circle is used to mean 'none' or 'nothing' elsewhere too.)
You can set or remove a triplet on a rest and a note or rest on either side by selecting the rest and clicking on the -3- symbol. See under modifying notes for more details.
Notes and chords
Since you can select single note heads, whole chords, or multiple chords, the modifications available will vary with the selection. Accidentals belong to individual note heads, while most other modifications apply to the whole chord if the head is part of a chord. You can select multiple chords and apply the same operation to all at once. A couple of operations only make sense if more than one note or chord is selected.
At the left of the tool pane there is a tool for swapping the stem direction of a note. This will swap all the notes in a beamed group if you select one note in the group.
Next is a tool for swapping between flags and beams. If you select some notes which are not beamed together and click here, SharpEye will attempt to join them. If you select one or more notes that are all within a beamed group, this will separate them into single notes with flags. The notes must all be in the same measure and stave.
You can set the number of dots as with rests.
You can change the duration by clicking on one of the note symbols.
You can set or remove a staccato, tenuto, pause, or accent. These toggle the symbol on or off.
You can set or remove a triplet by selecting the middle note and clicking on the -3- symbol. You cannot set the rarer kinds of irregular notes, though duplets can be mimicked using dotted notes. Note that when you change the time signature, SharpEye will recalculate which notes it thinks are triplets, and may override what you have done. You should therefore make sure the time signature is correct first. (It is sensible to get the time signature right first for other reasons too.)
If you have selected a single note head you can change its accidental, or remove any accidental by clicking on the empty circle.
To the right of the accidentals is a tool for vertically aligning selected notes. They must all be in the same measure, but not necessarily in the same stave. The horizontal positions of the selected notes will be averaged.
At the right end of the pane is a tool for adding and removing ties. If a note or chord has a tie to its right this will remove it. Otherwise SharpEye will try to add a tie from the note or chord.
Note that slurs are drawn in thin lines, and ties with thicker lines to help distinguish them. Also note that ties or slurs which are not attached at both ends are shown in grey. Ties and slurs can also be edited by dragging - see the next section.
Moving symbols
You can move some objects by dragging with the Select button.
Note heads can be moved up and down, and placed either side of the stem.
Rests can be moved freely, as long as they stay in the same measure and stave.
Clefs and key signatures can be moved horizontally, as long as they stay in the same measure and stave.
Lyric words can be moved horizontally within the same line.
Slurs can be moved within a system. If you drag near one end you will move that end; the other end stays fixed. If you drag near the middle you will be able to move the slur as a whole.
Creating symbols
You always use the Adjust button to insert things.
If you have been selecting things, the first Adjust click will not insert anything, but will show the insertion tool pane, with a symbol similar to the last selection highlighted. The insertion tool pane uses green symbols to distinguish it from the modification tool panes.
Choosing a symbol
There are so many possible variations of musical symbols that to show all of them would make things hard to find, or complicated to choose. Instead the insertion tool pane shows the basic kinds of symbol available. You should choose a symbol that is close to what you want and then modify it after inserting it.
For example, in order to insert a 3/4 time signature, you would choose the only time signature available in the tool pane (a 4/4) and insert that in the right place. Then select it with the mouse and change it to a 3/4 in the time signature tool pane. Bar lines work in a similar way.
The three shapes of clef can be chosen directly. If you need a tenor clef you need to insert an alto clef (C clef) and then change it.
There are two key signature symbols, one for flats and one for sharps, which insert a single sharp or flat. For keys with more than one sharp or flat, insert either of these then modify it. If you need a key change to the key of C insert either of these then change it by clicking on the natural sign in the key signature tool pane.
You can choose all the basic durations of rests, and add rhythm dots later if need be.
Notes and chords are a little more complex. You can only insert notes with flags, not beams. You can set the stem direction using the three symbols on the left (up stem, let SharpEye decide, down stem).
You can also add note heads to notes that are already there to make chords. For this use the symbol (which shows a single note and a two-note chord) just to the right of the notes and rests.
To insert a lyric word, choose the "la-la" symbol.
To insert a slur, choose one of the curves just below the "la-la" symbol.
When you have chosen a symbol to insert, the pointer will change to indicate this, but remember to use the Adjust button - the Select button will still select things.
Joining staves
It is sometimes necessary to join two adjacent staves in a system, usually because they are both to be played by one instrument (eg keyboard or harp). This enables SharpEye to analyse the rhythm properly, and will put both staves on the same MIDI channel.
The black rectangles at the start of the score are for joining staves. Initially these are horizontal, indicating the staves are separated. If you click on one, it will become vertical, joining a pair of staves. You can reverse the operation by clicking again.
It is not always necessary to join staves in keyboard music. Sometimes the right hand and left hand parts make sense independently. Occasions when it is necessary include:
(1) Where a single melody line is written on two staves, wandering between both, and with no rests to fill in the measures where no notes are sounding.
(2) When the main rhythm is given by the left hand part of a piece for keyboard, and notes are aligned with this in the top stave without rests or other notes to indicate when they sound.
If you're wondering what the circles at the start of the score are for, see under Saving music files.
Note for experts: It might seem better if SharpEye always looked at neighbouring staves in a system to analyse the rhythm. However there are problems with this approach as well. While the rule that notes that sound together should be vertically aligned is usually followed, it is not always the case in printed music, so this assumption can lead to errors too. Also, if SharpEye makes an error in one stave, it might spread into other staves if it relied too much on vertical alignment. Future versions may handle this differently.
Irregular Systems
If SharpEye finds systems with different numbers of staves in the page (or when appending, in the score) it will add extra empty staves at the bottom to make the score 'rectangular'. This may be correct, but often it isn't.
In order to deal with this, you can use the green arrows that are shown between systems. By default they join each stave to the corresponding one in the next system, ie, they are 'parallel'. If this is wrong, you can drag the arrow heads up or down to join the correct pairs of staves.
For example, it may be that all instruments are shown on the first system of a score, but on later systems, instruments are dropped if they are not playing at that point. SharpEye will add empty staves at the bottom, but unless it happens to be the bottom instrument that was dropped, this will mean that some instruments are mismatched. However, if you change the linking arrows you can correct this, by linking the missing instruments to the empty staves.
Not every score layout can be dealt with in this way, especially when an instrument or group of instruments uses a variable number of staves throughout the piece. In such a case you may have to deal with the score in sections and join them together with a music notation or MIDI editor.
Editing guidelines
If you're not sure how to go about checking and correcting a score, here are some suggestions.
Check the time signature(s) first. There's usually just one at the start of the music, but some music has changes in the middle. If there are warnings on most of the measures, the time signature is probably wrong.
Next check the clefs and key signatures. These usually occur at the left of each system, sometimes also in the middle. If you export and play the MIDI file, and it mostly sounds OK, but it sounds horrible for some section(s), its likely to be this kind of error.
Look at all the measures marked with warnings.
Remember that the warnings are like those from a spell checker and don't catch all errors. Proof-reading music to ensure there are no errors at all is difficult. Use your ears as well as your eyes.
If you have Rhapsody or a MIDI editor it is up to you how much editing you do in SharpEye and how much you leave to do later. It is almost essential to ensure the time signatures, clefs, key signatures and bar lines are correct before exporting, but detailed note editing can be done either way. If you export a score which contains gray notes they will not be put into the Rhapsody or MIDI file.
Keyboard shortcuts
There are some keyboard shortcuts using the function keys to speed up the process of correcting errors. Not everything can be done in this way, only the more common operations.
As usual, F3 brings up a save box to save the music. You can also bring up save boxes for saving in other formats as follows: Control-F3 for MIDI, Shift-F3 for Rhapsody, Control-Shift-F3 for PMS.
The other function keys only operate when inserting, and when modifying notes and rests. The keys F5 through F10 are assigned note durations as follows.
F5 F6 F7 F8 F9 F10
1/32 1/16 1/8 1/4 1/2 1
In insert mode, these select notes of these durations. In modify mode, they changed the selected rest or notes to these durations.
When in insert mode, F1 can be used to set the stem direction of the note to be inserted. F1 cycles through the three options. F11 selects the 'add head to chord' option.
When modifying notes, F1 swaps stem direction, F2 changes flags to beams or vice-versa, F4 cycles through zero, one or two rhythm dots, and F11 cycles through the common accidentals: none, sharp, flat, natural.
When modifying rests, F4 cycles through zero, one or two rhythm dots.
The following diagram summarises the shortcuts. The first row shows the ones for inserting. The other rows show the ones for modifying notes and rests.
Problems and Tips
Introduction
There is a lot of variety in musical scores: both the music itself and the styles and conventions used in the layout. There is much variation in the quality of printing. There are also a lot of scanners available, often with many options, which can be confusing. All this means you may have some difficulty getting SharpEye to work well.
This section tries to deal with the most common problems you're likely to encounter, and where possible, gives advice about dealing with them.
Limitations on notation recognised
This describes some limitations on the kind of music you can expect SharpEye to read.
It only recognises standard 5-line staves.
If it finds systems with different numbers of staves in the page (or when appending, in the score) it will add extra empty staves at the bottom to make the score 'rectangular'. This may be correct, but often it isn't. The safest is to deal with each section that contains a different number of staves separately, and join the results together in a MIDI editor. Facilities to deal with this situation more easily will be added to the music editor in the near future.
Chords and groups of beamed notes which span more than one stave are not read properly.
There are some limits on size - maximum 50 staves per system, maximum image size 15000 width by 30000 height - which are not likely to cause practical problems. Only 15 channels are exported as MIDI. (Channel 10 is avoided since it is usually used for percussion.)
Image quality
This attempts to give you an idea of the quality of images that you can expect SharpEye to read, and some hints on improving matters. See also the section on scanning. Note that these images are screen shots. It is important to compare them with what you see on screen in SharpEye's image window, at 100%.
In this image the staff lines are broken. SharpEye can cope with a certain amount of this but there are limits. This can be a problem with good quality printing if the lines are very thin. In such a case, a darker scan will usually improve things a great deal.
If the printing is faint (grey rather than black) you can get images like this. Some scanners have settings such as 'photo', 'halftone', or 'dithered' which attempt to represent grey areas with patterns of black dots. These make the problem worse, so should be turned off. A darker scan may help too, but you may find you get too much noise in the white areas if the original is too poor.
At some point this image has been converted to a low resolution and the shapes have become 'chunky' and the gaps between beams have been filled. (It may have been converted to a grey scale and back again, or faxed.) There isn't much you can do about this unless you can get a better version of the original.
Here the staves are wavy in the original, and nothing can be done about it.
All these images are 'borderline'. SharpEye may produce useful output on such images, but quite a lot of errors are likely. If you can't improve the quality of the scan, you may or may not find it worth using SharpEye: it depends on how fast you can enter music by other means.
Tips and techniques
Adding notes to the right stave
Sometimes, notes on ledger lines may be much nearer a neighbouring stave than the one they should belong to, which can cause a problem when inserting such notes.
When deciding which stave to insert a note into, SharpEye looks at symbols already belonging to each stave as well as the position of the staves themselves. So if there are already notes on ledger lines nearby it will usually add further notes to the correct stave. But if not, add the note near the correct stave, then drag it up or down to the right position.
Selecting overlapping note heads
When two note heads coincide (as when two voices sound together) you can select one head by clicking towards its stem. Eg, click just above the centre of the head to select the one with the up stem.
Partial measures
At the start of a score, and next to bar lines which are double lines, or repeat signs, there is a 'partial measure' which may or may not be a complete measure. In such cases SharpEye tries to guess the length by looking at the notes. This means that in such 'partial measures' the warnings may be confusing, and you need to check these areas carefully. The warnings should disappear when everything is right, but they may point to the wrong measure as being the source of the problem.
Split measures
Occasionally, scores are written with a measure split across two systems. SharpEye doesn't really understand such things, and will assume that there are two measures. However, if you make the bar line at the end of the first system a double bar line and make sure the notes are right, you should be able to get SharpEye to 'join' the two partial measures together.
Gray notes won't go
There can be several causes for this. Here are some things to check:
Vertical alignment
Sometimes notes which should sound together are not vertically aligned. SharpEye can still analyse some measures where this happens, but not all. You may have to move some notes to make things clear. If the heads overlap significantly, or the stems are very close, they will be regarded as sounding together. More rarely the opposite problem happens, and notes which should sound separately overlap enough to confuse SharpEye.
Missed notes in beamed groups
If SharpEye misses a note in the middle of a group of notes that are beamed together, it is not enough to just add a note of the right duration. You must also join it to the group.
Hidden overlaps
Occasionally, a symbol may be hidden by another symbol. When note heads are very close, a dot on a note may be hidden by another note head. Or a rest (eg whole or half note rest) may be hidden by something. If you can't guess what the problem is, you may have to delete symbols until you can see what is going on.
Incomplete voices
When there are two voices in one stave, and one of the voices is incomplete (ie it doesn't contain enough notes or rests to fill the measure) some of the notes may be grey. If the notes line up with ones in the other voice, SharpEye will understand them but if they don't line up, it won't. Here is a simple example. In order to make the quaver (eighth note) black, you can add rests to the up stem voice.
