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mirror of https://github.com/mstorsjo/fdk-aac.git synced 2024-12-12 08:26:11 +01:00

Merge "Fix huffman decoder escape sequence length limitation." am: a4d6ca7b07

am: ac56cddd1f

Change-Id: I422463f26359bef0ad3220c9324ceb26fcd1da14
This commit is contained in:
Fraunhofer IIS FDK 2018-11-05 15:14:17 -08:00 committed by android-build-merger
commit a16b4cba47

View File

@ -127,9 +127,11 @@ amm-info@iis.fraunhofer.de
The function reads the escape sequence from the bitstream, The function reads the escape sequence from the bitstream,
if the absolute value of the quantized coefficient has the if the absolute value of the quantized coefficient has the
value 16. value 16.
A limitation is implemented to maximal 31 bits to prevent endless loops. A limitation is implemented to maximal 21 bits according to
If it strikes, MAX_QUANTIZED_VALUE + 1 is returned, independent of the sign of ISO/IEC 14496-3:2009(E) 4.6.3.3.
parameter q. This limits the escape prefix to a maximum of eight 1's.
If more than eight 1's are read, MAX_QUANTIZED_VALUE + 1 is
returned, independent of the sign of parameter q.
\return quantized coefficient \return quantized coefficient
*/ */
@ -139,11 +141,11 @@ LONG CBlock_GetEscape(HANDLE_FDK_BITSTREAM bs, /*!< pointer to bitstream */
if (fAbs(q) != 16) return (q); if (fAbs(q) != 16) return (q);
LONG i, off; LONG i, off;
for (i = 4; i < 32; i++) { for (i = 4; i < 13; i++) {
if (FDKreadBit(bs) == 0) break; if (FDKreadBit(bs) == 0) break;
} }
if (i == 32) return (MAX_QUANTIZED_VALUE + 1); if (i == 13) return (MAX_QUANTIZED_VALUE + 1);
off = FDKreadBits(bs, i); off = FDKreadBits(bs, i);
i = off + (1 << i); i = off + (1 << i);