Podporovane typy kodu:
EAN_8, EAN_13, UPC_E, UPC_A, CODE_39, CODE_93, CODE_128, ITF, CODABAR,
QR_CODE, PDF_417, DATA_MATRIX, AZTEC 

Parametr "f" v URL urcuje typ generovaneho kodu. Neni-li zadan, je generovan QR kod.

Parametry pro jednotlive typy
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EAN_8, EAN_13, UPC_E, UPC_A, CODE_39, CODE_93, CODE_128, ITF, CODABAR
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- d  = hodnota, ktera bude zapsana v kodu

- m  = [volitelne] margin - minimalni odsazeni v pixelech.
       Specifies margin, in pixels, to use when generating the barcode.
       The meaning can varyby format; for example it controls margin before
       and after the barcode horizontally formost 1D formats.

- w  = [volitelne] width - sirka obrazku.

- h  = [volitelne] height - vyska obrazku.

EAN8
EAN13
UPC-E
UPC-A
CODE 39
CODE 93
CODE 128
ITF
CODABAR

QR_CODE
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- d  = text, ktery bude v QR kodu

- m  = [volitelne] margin - minimalni odsazeni v pixelech. Vychozi hodnota je 4.
       Specifies margin, in pixels, to use when generating the barcode.
       The meaning can vary by format; for example it controls margin before
       and after the barcode horizontally for most 1D formats.

- e  = [volitelne] error correction. ErrorCorrectionLevel.H, L, M, Q - vychozi je L.
       Specifies what degree of error correction to use, for example in QR Codes.
       Type depends on the encoder. For example for QR codes it's type ErrorCorrectionLevel.
       For Aztec it is of type Integer, representing the minimal percentage of error
       correction words. For PDF417 it is of type Integer, valid values being 0 to 8.
       In all cases, it can also be a String representation of the desired value as well.
       Note: an Aztec symbol should have a minimum of 25% EC words.

- s  = [volitelne] velikost obrazku. Cele cislo, ktere se pouzije pro sirku i vysku. Vychozi hodnota je 200.

- ch = [volitelne] znakova sada textu. Pokud URL parametr neobsahuje a neni mozne text kodovat v US-ASCII, pouzije se UTF-8.
       Nema-li se pouzita znakova data do QR kodu zapisovat [ECI], je nutne parametr
       v URL poslat s prazdnou hodnotou.
       
       Seznam moznych hodnot (case sensitive). Zdroj https://github.com/zxing/zxing/blob/master/core/src/main/java/com/google/zxing/common/CharacterSetECI.java
       
       Cp437
       ISO8859_1, ISO-8859-1
       ISO8859_2, ISO-8859-2
       ISO8859_3, ISO-8859-3
       ISO8859_4, ISO-8859-4
       ISO8859_5, ISO-8859-5
       ISO8859_6, ISO-8859-6
       ISO8859_7, ISO-8859-7
       ISO8859_8, ISO-8859-8
       ISO8859_9, ISO-8859-9
       ISO8859_10, ISO-8859-10
       ISO8859_11, ISO-8859-11
       ISO8859_13, ISO-8859-13
       ISO8859_14, ISO-8859-14
       ISO8859_15, ISO-8859-15
       ISO8859_16, ISO-8859-16
       SJIS, Shift_JIS
       Cp1250, windows-1250
       Cp1251, windows-1251
       Cp1252, windows-1252
       Cp1256, windows-1256
       UnicodeBigUnmarked, UTF-16BE, UnicodeBig
       UTF8, UTF-8
       ASCII, US-ASCII
       Big5
       GB18030, GB2312, EUC_CN, GBK
       EUC_KR, EUC-KR

QR CODE

PDF_417
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- d  = hodnota, ktera bude zapsana v kodu

- m  = [volitelne] margin - minimalni odsazeni v pixelech.

- w  = [volitelne] width - sirka obrazku.

- h  = [volitelne] height - vyska obrazku.

- ch = [volitelne] znakova sada textu. Pokud URL parametr neobsahuje a neni mozne text kodovat v US-ASCII, pouzije se UTF-8.
       Stejne hodnoty jako v popisu u QR kodu.
       
- e  = [volitelne] error correction. Cele cislo.
       PDF417 error correction level to use.
       Vice na https://en.wikipedia.org/wiki/PDF417

PDF417

DATA_MATRIX
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- d  = hodnota, ktera bude zapsana v kodu

- w  = [volitelne] width - sirka obrazku.

- h  = [volitelne] height - vyska obrazku.

- datamartixShape = [volitelne] styl kodu. Jedna z hodnot FORCE_NONE, FORCE_SQUARE, FORCE_RECTANGLE

DATA_MATRIX

AZTEC
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- d  = hodnota, ktera bude zapsana v kodu

- s  = [volitelne] velikost obrazku. Cele cislo, ktere se pouzije pro sirku i vysku. Vychozi hodnota je 200.

- ch = [volitelne] znakova sada textu. Pokud URL parametr neobsahuje a neni mozne text kodovat v US-ASCII, pouzije se UTF-8.
       Stejne hodnoty jako v popisu u QR kodu.

- e  = [volitelne] error correction. Cele cislo.
       Minimal percentage of error check words (According to ISO/IEC 24778:2008, a minimum of 23% + 3 words is recommended).

AZTEC