Said block will only be referenced by blocks from the same macroblock, which will read the new AC values instead of the reset values from this function.
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| @@ -506,7 +506,9 @@ void ff_clean_intra_table_entries(MpegEncContext *s) · 505 unmodified lines | |||
| 506 | /* ac pred */ | 506 | /* ac pred */ |
| 507 | int16_t (*ac_val)[16] = s->ac_val[0]; | 507 | int16_t (*ac_val)[16] = s->ac_val[0]; |
| 508 | av_assume(!((uintptr_t)ac_val & 0xF)); | 508 | av_assume(!((uintptr_t)ac_val & 0xF)); |
| 509 | memset(ac_val[xy ], 0, 2 * sizeof(*ac_val)); | 509 | // Don't reset the upper-left luma block, as it will only ever be |
| 510 | // referenced by blocks from the same macroblock. | ||
| 511 | memset(ac_val[xy + 1], 0, sizeof(*ac_val)); | ||
| 510 | memset(ac_val[xy + wrap], 0, 2 * sizeof(*ac_val)); | 512 | memset(ac_val[xy + wrap], 0, 2 * sizeof(*ac_val)); |
| 511 | /* ac pred */ | 513 | /* ac pred */ |
| 512 | memset(ac_val[uxy], 0, sizeof(*ac_val)); | 514 | memset(ac_val[uxy], 0, sizeof(*ac_val)); |