iTextSharp.text.pdf.BarcodePDF417.TextCompaction C# (CSharp) Метод

        private void TextCompaction(byte[] input, int start, int length) {
            int[] dest = new int[ABSOLUTE_MAX_TEXT_SIZE * 2];
            int mode = ALPHA;
            int ptr = 0;
            int fullBytes = 0;
            int v = 0;
            int k;
            int size;
            length += start;
            for (k = start; k < length; ++k) {
                v = GetTextTypeAndValue(input, length, k);
                if ((v & mode) != 0) {
                    dest[ptr++] = v & 0xff;
                    continue;
                }
                if ((v & ISBYTE) != 0) {
                    if ((ptr & 1) != 0) {
                        //add a padding word
                        dest[ptr++] = PAL;
                        mode = (mode & PUNCTUATION) != 0 ? ALPHA : mode;
                    }
                    dest[ptr++] = BYTESHIFT;
                    dest[ptr++] = v & 0xff;
                    fullBytes += 2;
                    continue;
                }
                switch (mode) {
                case ALPHA:
                    if ((v & LOWER) != 0) {
                        dest[ptr++] = LL;
                        dest[ptr++] = v & 0xff;
                        mode = LOWER;
                    }
                    else if ((v & MIXED) != 0) {
                        dest[ptr++] = ML;
                        dest[ptr++] = v & 0xff;
                        mode = MIXED;
                    }
                    else if ((GetTextTypeAndValue(input, length, k + 1) & GetTextTypeAndValue(input, length, k + 2) & PUNCTUATION) != 0) {
                        dest[ptr++] = ML;
                        dest[ptr++] = PL;
                        dest[ptr++] = v & 0xff;
                        mode = PUNCTUATION;
                    }
                    else {
                        dest[ptr++] = PS;
                        dest[ptr++] = v & 0xff;
                    }
                    break;
                case LOWER:
                    if ((v & ALPHA) != 0) {
                        if ((GetTextTypeAndValue(length, k + 1) & GetTextTypeAndValue(length, k + 2) & ALPHA) != 0) {
                            dest[ptr++] = ML;
                            dest[ptr++] = AL;
                            mode = ALPHA;
                        }
                        else {
                            dest[ptr++] = AS;
                        }
                        dest[ptr++] = v & 0xff;
                    }
                    else if ((v & MIXED) != 0) {
                        dest[ptr++] = ML;
                        dest[ptr++] = v & 0xff;
                        mode = MIXED;
                    }
                    else if ((GetTextTypeAndValue(input, length, k + 1) & GetTextTypeAndValue(input, length, k + 2) & PUNCTUATION) != 0) {
                        dest[ptr++] = ML;
                        dest[ptr++] = PL;
                        dest[ptr++] = v & 0xff;
                        mode = PUNCTUATION;
                    }
                    else {
                        dest[ptr++] = PS;
                        dest[ptr++] = v & 0xff;
                    }
                    break;
                case MIXED:
                    if ((v & LOWER) != 0) {
                        dest[ptr++] = LL;
                        dest[ptr++] = v & 0xff;
                        mode = LOWER;
                    }
                    else if ((v & ALPHA) != 0) {
                        dest[ptr++] = AL;
                        dest[ptr++] = v & 0xff;
                        mode = ALPHA;
                    }
                    else if ((GetTextTypeAndValue(input, length, k + 1) & GetTextTypeAndValue(input, length, k + 2) & PUNCTUATION) != 0) {
                        dest[ptr++] = PL;
                        dest[ptr++] = v & 0xff;
                        mode = PUNCTUATION;
                    }
                    else {
                        dest[ptr++] = PS;
                        dest[ptr++] = v & 0xff;
                    }
                    break;
                case PUNCTUATION:
                    dest[ptr++] = PAL;
                    mode = ALPHA;
                    --k;
                    break;
                }
            }
            if ((ptr & 1) != 0)
                dest[ptr++] = PS;
            size = (ptr + fullBytes) / 2;
            if (size + cwPtr > MAX_DATA_CODEWORDS) {
                throw new ArgumentOutOfRangeException("The text is too big.");
            }
            length = ptr;
            ptr = 0;
            while (ptr < length) {
                v = dest[ptr++];
                if (v >= 30) {
                    codewords[cwPtr++] = v;
                    codewords[cwPtr++] = dest[ptr++];
                }
                else
                    codewords[cwPtr++] = v * 30 + dest[ptr++];
            }
        }