[FFmpeg-devel] [PATCH] vp3data, mpc8huff: Make some arrays unsigned to prevent overflow

Peter Ross pross at xvid.org
Sun Jul 21 07:07:07 EEST 2019


On Sat, Jul 20, 2019 at 03:51:25PM +0200, Andreas Rheinhardt wrote:
> Some of the VP3 arrays (namely vp31_intra_y_dequant, vp31_intra_c_dequant
> and vp31_inter_dequant) are currently declared as array of (const) int8_t
> despite them being only used to directly initialize an array of uint8_t.
> vp31_inter_dequant even contains the value 128 which is not
> representible in int8_t and might generate overflow warnings by
> compilers.
> 
> Similarly, mpc8_q4_syms is an array of int8_t that is initialized using
> values not in the range of an int8_t and that is only accessed via
> a pointer to uint8_t in ff_init_vlc_sparse. The latter applies to all
> the other *_bits and *_syms tables in mpc8huff.h, so make them all
> unsigned.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
> ---
>  libavcodec/mpc8huff.h | 34 +++++++++++++++++-----------------
>  libavcodec/vp3data.h  |  6 +++---
>  2 files changed, 20 insertions(+), 20 deletions(-)
> 
> diff --git a/libavcodec/mpc8huff.h b/libavcodec/mpc8huff.h
> index 8491037aa4..0566c910ca 100644
> --- a/libavcodec/mpc8huff.h
> +++ b/libavcodec/mpc8huff.h
> @@ -34,7 +34,7 @@ static const uint8_t mpc8_bands_codes[MPC8_BANDS_SIZE] = {
>   0x08, 0x09, 0x06, 0x07, 0x05, 0x05, 0x03, 0x03,
>   0x01,
>  };
> -static const int8_t mpc8_bands_bits[MPC8_BANDS_SIZE] = {
> +static const uint8_t mpc8_bands_bits[MPC8_BANDS_SIZE] = {
>    1,  3,  5,  6,  7,  8,  8,  9,
>   10, 11, 12, 12, 12, 13, 12, 12,
>   12, 12, 12, 13, 12, 12, 12, 11,
> @@ -48,7 +48,7 @@ static const int8_t mpc8_bands_bits[MPC8_BANDS_SIZE] = {
>  static const uint8_t mpc8_scfi0_codes[MPC8_SCFI0_SIZE] = {
>   0x00, 0x01, 0x01, 0x01,
>  };
> -static const int8_t mpc8_scfi0_bits[MPC8_SCFI0_SIZE] = {
> +static const uint8_t mpc8_scfi0_bits[MPC8_SCFI0_SIZE] = {
>    3,  3,  1,  2,
>  };
>  
> @@ -60,7 +60,7 @@ static const uint8_t mpc8_scfi1_codes[MPC8_SCFI1_SIZE] = {
>   0x04, 0x06, 0x02, 0x02, 0x05, 0x07, 0x03, 0x03,
>  
>  };
> -static const int8_t mpc8_scfi1_bits[MPC8_SCFI1_SIZE] = {
> +static const uint8_t mpc8_scfi1_bits[MPC8_SCFI1_SIZE] = {
>    6,  7,  6,  6,  7,  5,  5,  5,
>    6,  5,  2,  3,  6,  5,  3,  2,
>  
> @@ -79,7 +79,7 @@ static const uint8_t mpc8_dscf0_codes[MPC8_DSCF0_SIZE] = {
>   0x0C, 0x0D, 0x07, 0x08, 0x09, 0x06, 0x07, 0x03,
>   0x04, 0x05, 0x00, 0x01, 0x02, 0x03, 0x04, 0x05,
>  };
> -static const int8_t mpc8_dscf0_bits[MPC8_DSCF0_SIZE] = {
> +static const uint8_t mpc8_dscf0_bits[MPC8_DSCF0_SIZE] = {
>   12, 12, 12, 11, 11, 11, 10, 10,
>   10, 10, 10,  9,  9,  9,  9,  8,
>    8,  8,  8,  7,  7,  7,  7,  6,
> @@ -105,7 +105,7 @@ static const uint8_t mpc8_dscf1_codes[MPC8_DSCF1_SIZE] = {
>   0x05, 0x06, 0x07, 0x01, 0x02, 0x03, 0x04, 0x05,
>   0x0D,
>  };
> -static const int8_t mpc8_dscf1_bits[MPC8_DSCF1_SIZE] = {
> +static const uint8_t mpc8_dscf1_bits[MPC8_DSCF1_SIZE] = {
>   15, 14, 14, 13, 13, 13, 12, 12,
>   12, 12, 11, 11, 11, 11, 10, 10,
>   10, 10,  9,  9,  9,  8,  8,  7,
> @@ -132,7 +132,7 @@ static const uint8_t mpc8_res_codes[2][MPC8_RES_SIZE] = {
>      0x03,
>    }
>  };
> -static const int8_t mpc8_res_bits[2][MPC8_RES_SIZE] = {
> +static const uint8_t mpc8_res_bits[2][MPC8_RES_SIZE] = {
>    {
>       1,  2,  4,  5,  6,  7,  9, 10,
>      11, 12, 13, 14, 15, 16, 16,  8,
> @@ -153,7 +153,7 @@ static const uint8_t mpc8_q1_codes[MPC8_Q1_SIZE] = {
>   0x03, 0x04, 0x05, 0x01, 0x01, 0x01, 0x01, 0x01,
>   0x01, 0x00, 0x01,
>  };
> -static const int8_t mpc8_q1_bits[MPC8_Q1_SIZE] = {
> +static const uint8_t mpc8_q1_bits[MPC8_Q1_SIZE] = {
>    6,  4,  4,  3,  3,  3,  3,  3,
>    4,  4,  4,  5,  7,  8,  9, 10,
>   11, 12, 12,
> @@ -196,7 +196,7 @@ static const uint8_t mpc8_q9up_codes[MPC8_Q9UP_SIZE] = {
>   0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,
>   0x4A, 0x4B, 0x06, 0x07, 0x08, 0x09, 0x00, 0x01,
>  };
> -static const int8_t mpc8_q9up_bits[MPC8_Q9UP_SIZE] = {
> +static const uint8_t mpc8_q9up_bits[MPC8_Q9UP_SIZE] = {
>   10, 10, 10, 10, 10,  9,  9,  9,
>    9,  9,  9,  9,  9,  9,  9,  9,
>    9,  9,  9,  8,  8,  9,  9,  9,
> @@ -272,7 +272,7 @@ static const uint8_t mpc8_q2_codes[2][MPC8_Q2_SIZE] = {
>   0x03, 0x1C, 0x17, 0x1D, 0x05,
>  }
>  };
> -static const int8_t mpc8_q2_bits[2][MPC8_Q2_SIZE] = {
> +static const uint8_t mpc8_q2_bits[2][MPC8_Q2_SIZE] = {
>  {
>   12, 11, 10, 11, 13, 11,  9,  8,
>    9, 11, 11,  8,  7,  8, 11, 11,
> @@ -324,7 +324,7 @@ static const uint8_t mpc8_q3_codes[MPC8_Q3_SIZE] = {
>   0x06, 0x05, 0x04, 0x03, 0x02, 0x03, 0x02, 0x01,
>   0x00,
>  };
> -static const int8_t mpc8_q3_bits[MPC8_Q3_SIZE] = {
> +static const uint8_t mpc8_q3_bits[MPC8_Q3_SIZE] = {
>    3,  4,  4,  4,  4,  4,  4,  5,
>    5,  5,  5,  5,  5,  6,  6,  6,
>    6,  6,  6,  6,  6,  6,  6,  6,
> @@ -333,7 +333,7 @@ static const int8_t mpc8_q3_bits[MPC8_Q3_SIZE] = {
>    8,  8,  8,  8,  8,  9,  9,  9,
>    9,
>  };
> -static const int8_t mpc8_q3_syms[MPC8_Q3_SIZE] = {
> +static const uint8_t mpc8_q3_syms[MPC8_Q3_SIZE] = {
>     48,    65,    64,    49,    63,    32,    47,    80,
>     79,    50,    62,    33,    16,    82,    81,    95,
>     94,    66,    78,    34,    46,    17,    31,    30,
> @@ -360,7 +360,7 @@ static const uint8_t mpc8_q4_codes[MPC8_Q4_SIZE] = {
>   0x06, 0x05, 0x04, 0x03, 0x02, 0x03, 0x02, 0x01,
>   0x00,
>  };
> -static const int8_t mpc8_q4_bits[MPC8_Q4_SIZE] = {
> +static const uint8_t mpc8_q4_bits[MPC8_Q4_SIZE] = {
>    4,  5,  5,  5,  5,  5,  5,  5,
>    5,  5,  5,  5,  5,  6,  6,  6,
>    6,  6,  6,  6,  6,  6,  6,  6,
> @@ -373,7 +373,7 @@ static const int8_t mpc8_q4_bits[MPC8_Q4_SIZE] = {
>    9,  9,  9,  9,  9, 10, 10, 10,
>   10,
>  };
> -static const int8_t mpc8_q4_syms[MPC8_Q4_SIZE] = {
> +static const uint8_t mpc8_q4_syms[MPC8_Q4_SIZE] = {
>     64,    96,    81,    80,    95,    66,    65,    79,
>     78,    49,    48,    63,    32,   113,   112,    98,
>     97,   111,   110,    83,    82,    94,    93,    67,
> @@ -401,7 +401,7 @@ static const uint8_t mpc8_q5_codes[2][MPC8_Q5_SIZE] = {
>   0x06, 0x07, 0x04, 0x05, 0x03, 0x02, 0x03,
>  }
>  };
> -static const int8_t mpc8_q5_bits[2][MPC8_Q5_SIZE] = {
> +static const uint8_t mpc8_q5_bits[2][MPC8_Q5_SIZE] = {
>  {
>    7,  7,  6,  5,  4,  3,  3,  2,
>    3,  3,  4,  5,  6,  7,  7,
> @@ -430,7 +430,7 @@ static const uint8_t mpc8_q6_codes[2][MPC8_Q6_SIZE] = {
>   0x06, 0x07, 0x05, 0x06, 0x07, 0x02, 0x03,
>  }
>  };
> -static const int8_t mpc8_q6_bits[2][MPC8_Q6_SIZE] = {
> +static const uint8_t mpc8_q6_bits[2][MPC8_Q6_SIZE] = {
>  {
>    9,  9,  9,  9,  8,  8,  7,  6,
>    6,  6,  5,  5,  4,  4,  3,  2,
> @@ -471,7 +471,7 @@ static const uint8_t mpc8_q7_codes[2][MPC8_Q7_SIZE] = {
>   0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x02, 0x03,
>  }
>  };
> -static const int8_t mpc8_q7_bits[2][MPC8_Q7_SIZE] = {
> +static const uint8_t mpc8_q7_bits[2][MPC8_Q7_SIZE] = {
>  {
>   10, 10, 10,  9,  9, 10, 10, 10,
>   10, 10,  9,  9,  9,  9,  8,  8,
> @@ -536,7 +536,7 @@ static const uint8_t mpc8_q8_codes[2][MPC8_Q8_SIZE] = {
>   0x27, 0x28, 0x29, 0x04, 0x05, 0x06, 0x07,
>  }
>  };
> -static const int8_t mpc8_q8_bits[2][MPC8_Q8_SIZE] = {
> +static const uint8_t mpc8_q8_bits[2][MPC8_Q8_SIZE] = {
>  {
>   11, 11, 10, 10, 10, 10, 10,  9,
>   10,  9, 10, 12, 12, 11, 11, 11,
> diff --git a/libavcodec/vp3data.h b/libavcodec/vp3data.h
> index d520a10c76..3f24d5f7f6 100644
> --- a/libavcodec/vp3data.h
> +++ b/libavcodec/vp3data.h
> @@ -26,7 +26,7 @@
>  
>  /* these coefficients dequantize intraframe Y plane coefficients
>   * (note: same as JPEG) */
> -static const int8_t vp31_intra_y_dequant[64] = {
> +static const uint8_t vp31_intra_y_dequant[64] = {
>      16, 11, 10, 16,  24,  40,  51,  61,
>      12, 12, 14, 19,  26,  58,  60,  55,
>      14, 13, 16, 24,  40,  57,  69,  56,
> @@ -39,7 +39,7 @@ static const int8_t vp31_intra_y_dequant[64] = {
>  
>  /* these coefficients dequantize intraframe C plane coefficients
>   * (note: same as JPEG) */
> -static const int8_t vp31_intra_c_dequant[64] = {
> +static const uint8_t vp31_intra_c_dequant[64] = {
>      17, 18, 24, 47, 99, 99, 99, 99,
>      18, 21, 26, 66, 99, 99, 99, 99,
>      24, 26, 56, 99, 99, 99, 99, 99,
> @@ -51,7 +51,7 @@ static const int8_t vp31_intra_c_dequant[64] = {
>  };
>  
>  /* these coefficients dequantize interframe coefficients (all planes) */
> -static const int8_t vp31_inter_dequant[64] = {
> +static const uint8_t vp31_inter_dequant[64] = {
>      16, 16, 16, 20, 24, 28,  32,  40,
>      16, 16, 20, 24, 28, 32,  40,  48,
>      16, 20, 24, 28, 32, 40,  48,  64,
> -- 
> 2.21.0

okay on the vp3 patch.
in principal, mpc8 huff changes look good, but i am not familar with the codec.

-- Peter
(A907 E02F A6E5 0CD2 34CD 20D2 6760 79C5 AC40 DD6B)
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