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Merge branch 'v0.23.x'

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This commit is contained in:
Max Kellermann
2023-06-02 14:36:02 +02:00
parent 45f81cde6d 561d6fd478
commit 9c19368fc7
11 changed files with 59 additions and 15 deletions
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16
src/decoder/plugins/MadDecoderPlugin.cxx
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@@ -546,7 +546,21 @@ parse_lame(struct lame *lame, struct mad_bitptr *ptr, int *bitlen) noexcept
mad_bit_skip(ptr, 16);
lame->peak = MAD_F(mad_bit_read(ptr, 32) << 5); /* peak */
/* The lame peak value is a float multiplied by 2^23 and stored as an
* unsigned integer (it is always positive). MAD's fixed-point format uses
* 28 bits for the fractional part, so shift the 23 bit fraction up before
* converting to a float.
*/
unsigned long peak_int = mad_bit_read(ptr, 32);
#define LAME_PEAK_FRACBITS 23
#if MAD_F_FRACBITS > LAME_PEAK_FRACBITS
peak_int <<= (MAD_F_FRACBITS - LAME_PEAK_FRACBITS);
#elif LAME_PEAK_FRACBITS > MAD_F_FRACBITS
peak_int >>= (LAME_PEAK_FRACBITS - MAD_F_FRACBITS);
#endif
lame->peak = mad_f_todouble(peak_int); /* peak */
FmtDebug(mad_domain, "LAME peak found: {}", lame->peak);
lame->track_gain = 0;