java - Google Zxing library NotFoundException on valid QR code -


i'm using zxing java library encode , decode qr code in application goal store on printed paper critical information, small database (less 200 kb) spliting data in 2kb blocks , generating as qrcode required. i'm using latest zxing library available downloaded maven repository : zxing-core-3.3.0.

i found random failure build little program generate randomly byte array, convert base64 ascii chars , try encode/decome them. isolated data combination fails :

public class qr4jerrormain {    private static bufferedimage buffer;    public static void main(string[] args) {     try {         string encodetext = "tsighjcuhuxlu7l8czj31+mpc9c50h/cat7co5/wvicofzkso63q5orutsrfi+4/"                 + "0chmlki4iggksiphoy7rqyzbugor58pbshb4lzlxo6nneg64bdg5rstidnczcrhldy9ir2whar"                 + "pihqvfeimebcmrf0xmcaoptremcxknxmhaxwlqw4sq1/etojfizdpe7/uoimhjusxdhfpeokr+"                 + "0batc7pxfym4tsmjne036gzsdl4tijf57w8wgkllozlfm3tyr06ousig345zms6+g9rlbtwkcn"                 + "arjaon42hsybzyrx0y1pfm94d0xs4wdb24cyfex/9cu3avlzcc3tx8zqqnqzbsb6xrtjshdxud"                 + "onodkxlprxvpcoaa6v9qzf92irdaqje/elx6kyrnt8tcfoekgn4tske7twpbybanx6jg6dxcpc"                 + "m9d4+p+kgjc/28trc1hwu33dqlqko24csjcyliymj4vn4bhld4qmkhci0wbieuqwkqwinptdnl"                 + "ajngxybbrh4kre2nicumfwn5zpnnczr3ocq4zd8zwgukdymdebxqdcwxgx4yboky6hqnzte4lh"                 + "n2zsrkuh";          // create qr         boolean encodestatus = createqr2(encodetext);          if(!encodestatus) {             system.err.println("error while creating qr");         }          // read qr         string result = readqr2();          // compare data         boolean equals = arrays.equals(encodetext.getbytes(), result.getbytes());     }     catch(exception exc) {         exc.printstacktrace();     }   }     private static final boolean createqr2(string text/*, string filename*/) {     try {         // bitmatrix         bitmatrix bm = new qrcodewriter().encode(text, barcodeformat.qr_code, 50, 50);         // encode text qr code export image         buffer = new bufferedimage(bm.getwidth(), bm.getheight(), bufferedimage.type_int_rgb);          // fill pixels qr data         for(int ii = 0; ii < bm.getwidth(); ii++) {             for(int jj = 0; jj < bm.getheight(); jj++) {                 buffer.setrgb(ii, jj, bm.get(ii, jj) ? color.black.getrgb() : color.white.getrgb());             }         }          // optional write image bitmap file         return imageio.write(buffer, "bmp", new file("failureqr.bmp"));     }     catch(exception exc) {         exc.printstacktrace();         return false;     }   }     private static final string readqr2() throws exception {     luminancesource ls = new bufferedimageluminancesource(buffer);     binarybitmap binbitmap = new binarybitmap(new hybridbinarizer(ls));     system.out.println("are binarybitmap equals ? " + bitmatrix.equals(binbitmap.getblackmatrix()));     result result = new qrcodereader().decode(binbitmap);     return result.gettext();   } }

if run code, produce following 93*93 qr code:

failureqr.bmp

this piece of code throws com.google.zxing.formatexception exception without details.

as can see in code, not use bitmap file decode qr (to remove uncertainty picture write/read method). use directly same bufferedimage object in memory created previously. (using bitmap file leads same result)

the qr code valid, can decoded smartphone app, , give same text input.

so, why there trouble input data? should (or not do) have reliable decoding solution?

edit: same dataset encoded/decoded aztec or pdf_417 barcode format works.

edit2: updated method readqr2() , both bitmatrix objects equals. issue not coming image parser, comes qrcodereader.decode() itself.


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