CD-ROM Mode 1

98 (24B) Frames = 1 Block = 2352 bytes. Every Frame is protected by 8 Parity bytes.

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These 8 bytes, the 1st level of error correction, are CIRC generated. CD-ROM Mode 1 also adds a 2nd level of error correction, within each Block: 4 bytes to perform CRC to detect errors and 276 bytes, generated by RSPC, to detect and correct errors.

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12B + 4B + 2048B + 4B + 8B + 276B = 2352B

So, CD-ROM mode 1 uses 2 levels of error correction.
Level 1: every Frame is protected by 8B Parity, just like CD-DA.
Level 2: within each block, 2048B User Date is protected by 4B EDC and 276B ECC.

98 * 8B Parity + 4B EDC + 276B ECC = 788 bytes of CIRC/CRC/RSPC per 2048 bytes User Data


1 Frame = 2064B = 4B + 2B + 6B + 2048B + 4B

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1 Block = 37856B = 16 Frames + 2752B PO + 2080B PI

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16 * 4B EDC + 2752B PO + 2080B PI = 4836 bytes of CRC/RSPC per 32768 bytes User Data

4836B CRC/RSPC per 32768B < 788B CIRC/CRC/RSPC per 2048B

If this is correct, then CD-ROM Mode 1 uses relatively more bytes for EDC/ECC than DVD. Therefore it looks like CD-ROM Mode 1 has superior error correction over DVDs. But the following sources state otherwise:

Is the DVD error protection scheme, while being simpler, really able to achieve a better BER (Bit Error Rate) than CD-ROM Mode 1? If so, then how is this possible?

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