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b8861e3f09
The ARMv5E dewindowing routine takes 16 of each product's bits, rounded down, so each sum of 24 products came out about 12 units low. Through the filter bank that put a dc offset of about 12 LSB (of 16 bits) on the output and, from the high band, a tone at half the sample rate; together they were four fifths of the decoder's error on these targets. Start the sums 12 up. Also correct a comment in both ARM files. Checked with perfsim (Sansa Clip+ build) against ffmpeg's decode of seven files: the dc offset goes from 11 to 12 LSB down to under 1 LSB, and the error from about -66 dBFS to -69 to -72 dBFS, the same as the ARMv4 routine gives. Decoding is 0.7% slower (26.73 to 26.91 MHz for atrac3_lp2_132.oma). The ARMv4 output is unchanged. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> |
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| arm_support | ||
| fixedpoint | ||
| libsetjmp | ||
| microtar | ||
| mipsunwinder | ||
| rbcodec | ||
| skin_parser | ||
| tlsf | ||
| unwarminder | ||
| utf8proc | ||