Font Convert Tool

Note

This chapter introduces the standalone font conversion tool (exe program), which needs to be downloaded and run separately.

Font conversion tool functionality: Obtain all characters to be converted and their corresponding Unicode codes from a standard internal code page file, custom Unicode code page (or supplementary code page .txt file, custom .cst file). Find the corresponding character's vector font data from the font file (such as .ttf) based on the Unicode encoding. Convert it into bitmap format fonts or pre-processed vector fonts, and output as a .bin file.

Font Convert Tool Flowchart

Font Bin Generation

Please refer to the following steps for how to generate files:

1. Copy the Font library file to the directory \FontConvertTool\font.

Copy Font Library File

2. Please refer to the documentation under the directory \FontConvertTool\doc for the specific meanings of each parameter to configure font parameters by editing FontConfig.json.

Edit FontConfig.json File

3. Please open setting.ini and modify the optional configuration items.

Edit Setting.ini File

4. Double-click or execute via command line fontDirctionary.exe to generate font.bin.

Generate Font.bin File

FontConfig.json Parameter Description

FontConfig.json parameter description

Field name	Field meaning
OutputFolder	Tool output path. If the path does not exist, it will be created directly.
codePages	A list of selected characters arranged in a specific order for the text of a language. Multiple sets can be configured.
cstPaths	Binary Unicode code point CST file path. Multiple paths can be set. Commonly uses standard range set representation.
customerVals	User-defined continuous Unicode characters. Multiple groups can be set.
firstVal	The starting value of a custom continuous Unicode character.
range	A custom number of consecutive Unicode characters.
symbolPaths	Character set file path. Supports direct character reading and hexadecimal Unicode encoding formats. Multiple groups.
fontSet	Used to specify font-related settings to be converted.
bold	Specifies whether converted characters are bolded.
italic	Specifies whether the converted characters are slanted.
fontSize	Specifies the converted character size.
font	Specifies the font file to use for the conversion. Supports relative paths and automatic file name retrieval.
renderMode	Specifies how many bits are used to represent a pixel in the converted character bitmap. Supports 1/2/4/8.
indexMethod	Specifies the index mode of the output bin file. 0 for address index, 1 for offset index.
crop	Compresses font file size. Always on is recommended. Currently only crop with IndexMethod=0 is supported.
outputFormat	Font output format. 0 for bitmap font, 1 for vector font.

Setting.ini Parameter Description

Setting.ini parameter description

gamma	1	The gamma value is a parameter used to describe the nonlinear relationship between input pixel values and output brightness. The higher the value, the higher the text brightness.
rotate	0	Font Rotation Angle. 0: No rotation. 1: Rotate 90° clockwise. 2: Rotate 90° counterclockwise.

Font Size Evaluation

Different font configurations produce different file sizes, affecting Flash storage space usage. Here are size references for common configurations:

Common Scenario Recommendations

Recommended font configurations for common scenarios (Default: 24pt font, 2bpp)

Use Case	Character Set	Font Size	Bit Depth	Char Count	Size (KB)
Simple English UI	ASCII	24	2bpp	95	14.15
Western Languages	ISO8859-1	24	2bpp	193	28.69
Basic Chinese UI	GB2312	24	2bpp	7,478	749.03
Full Chinese UI	CP936(GBK)	24	2bpp	21,886	1,717.88
Basic Japanese UI	CP932	24	2bpp	7,483	746.16
Basic Korean UI	KSX1001	24	2bpp	8,187	793.48

Character Set Comparison

Different character set types contain vastly different numbers of characters, directly affecting file size. Choosing the appropriate character set based on application requirements can effectively balance functionality and storage space.

Character Set Description

Latin

• Lite (ASCII): 95 characters, includes basic English letters, numbers and common symbols, suitable for English-only interfaces

• Mid (ISO8859-1): 193 characters, includes Western European language characters (French, German, Spanish, etc.), suitable for multi-language European markets

• Full (UNICODE): 3,006 characters, includes complete Latin extended character set, suitable for global applications

Chinese

• Lite (GB2312): 7,478 characters, includes commonly used Simplified Chinese characters (Level-1: 3,755 + Level-2: 3,008) and symbols, suitable for basic Chinese interfaces

• Mid (CP936/GBK): 21,886 characters, includes all GB2312 characters plus Traditional Chinese and rare characters, suitable for complete Chinese support

• Full (UNICODE): 30,445 characters, includes CJK Unified Ideographs, suitable for multi-language mixed display

Japanese

• Lite (CP932): 7,483 characters, includes Japanese kana, common kanji (JIS Level-1 and Level-2) and symbols, suitable for basic Japanese interfaces

• Mid (CP932): 7,483 characters, same as Lite, CP932 already includes common Japanese characters

• Full (UNICODE): 16,077 characters, includes complete Japanese character set and extended kanji, suitable for professional Japanese applications

Korean

• Lite (KSX1001): 8,187 characters, includes Korean syllables, common hanja and symbols, suitable for basic Korean interfaces

• Mid (CP949): 17,106 characters, includes complete Korean syllables (11,172) and extended hanja, suitable for standard Korean applications

• Full (UNICODE): 22,862 characters, includes complete Korean character set, suitable for professional Korean applications

Character Set Size Comparison (24pt font, 2bpp)

Language	Lite Char Count	Size(KB)	Mid Char Count	Size(KB)	Full Char Count
Latin	95	14.15	193	28.69	3,006
Chinese	7,478	749.03	21,886	1,717.88	30,445
Japanese	7,483	746.16	7,483	746.16	16,077
Korean	8,187	793.48	17,106	1,156.32	22,862

Bit Depth Impact

Bit depth determines font display quality and file size:

• 1bpp: Black and white display, smallest file size, suitable for simple interfaces

• 2bpp: 4-level grayscale, smaller file size, good display quality, recommended for general applications (best cost-performance ratio)

• 4bpp: 16-level grayscale, medium file size, excellent display quality, suitable for high-quality interfaces

• 8bpp: 256-level grayscale, largest file size, best display quality, suitable for premium products

Bit Depth Size Comparison (Chinese GB2312, 24pt font, 7478 characters)

Bit Depth	1bpp	2bpp	4bpp	8bpp
Size(KB)	501.98	749.03	1,192.22	2,070.20
Ratio	0.67x	1x	1.59x	2.76x

Font Size Impact

Larger font sizes result in larger file sizes. Theoretically, file size grows quadratically with font size (doubling the font size results in approximately 4x file size), but due to compression techniques, the impact of doubling font size is somewhat mitigated.

Font Size Comparison (Lite character set, 2bpp bit depth)

Language	Font Size	Character Set	Char Count	Size(KB)	Ratio
Latin	16	ASCII	95	6.73	0.48x
Latin	24	ASCII	95	14.15	1x
Latin	32	ASCII	95	24.54	1.73x
Chinese	16	GB2312	7,478	532.40	0.71x
Chinese	24	GB2312	7,478	749.03	1x
Chinese	32	GB2312	7,478	1,181.83	1.58x

Vector Fonts

The main advantage of vector fonts is that they can be scaled arbitrarily, enabling multi-size reuse without generating separate font files for each size. However, file sizes are usually larger than bitmap fonts.

Vector Font Size Reference

Language	Character Set	Char Count	Size (KB)
Latin	Lite	95	10.56
Latin	Mid	193	25.62
Chinese	Lite	7,478	2,587.86
Japanese	Lite	7,483	2,782.93
Korean	Lite	8,187	2,558.50

Selection Guidelines

Choose appropriate font configuration based on application requirements:

1. Limited Storage: Choose Lite character set + 1bpp bit depth

2. Display Quality Priority: Choose 4bpp or 8bpp bit depth

3. Multi-language Support: Choose multiple font files combination (e.g., Latin + Chinese)

4. Multi-size Requirements: Choose multiple font files or vector fonts for arbitrary scaling and reuse

5. Balanced Solution: Mid character set + 2bpp bit depth