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avcodec/speedhqenc: Hardcode table to save space

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The SpeedHQ encoder currently reverses the entries of two small tables
and stores them in other tables. These other tables have a size of 48
bytes, yet the code for their initialization takes 135 bytes (GCC 9.3,
x64, O3 albeit in an av_cold function). So remove the runtime
initialization and hardcode the tables.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
This commit is contained in:
Andreas Rheinhardt 2020-12-10 09:19:08 +01:00 committed by Andreas Rheinhardt
parent b05631f7b9
commit 03008c2811
1 changed files with 7 additions and 24 deletions
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31
libavcodec/speedhqenc.c
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@ -38,8 +38,13 @@
extern RLTable ff_rl_speedhq;
static uint8_t speedhq_static_rl_table_store[2][2*MAX_RUN + MAX_LEVEL + 3];
static uint16_t mpeg12_vlc_dc_lum_code_reversed[12];
static uint16_t mpeg12_vlc_dc_chroma_code_reversed[12];
/* Exactly the same as MPEG-2, except little-endian. */
static const uint16_t mpeg12_vlc_dc_lum_code_reversed[12] = {
0x1, 0x0, 0x2, 0x5, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF
};
static const uint16_t mpeg12_vlc_dc_chroma_code_reversed[12] = {
0x0, 0x2, 0x1, 0x3, 0x7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF
};
/* simple include everything table for dc, first byte is bits
* number next 3 are code */
@ -48,30 +53,8 @@ static uint32_t speedhq_chr_dc_uni[512];
static uint8_t uni_speedhq_ac_vlc_len[64 * 64 * 2];
static uint32_t reverse(uint32_t num, int bits)
{
return bitswap_32(num) >> (32 - bits);
}
static void reverse_code(const uint16_t *code, const uint8_t *bits,
uint16_t *reversed_code, int num_entries)
{
for (int i = 0; i < num_entries; i++)
reversed_code[i] = reverse(code[i], bits[i]);
}
static av_cold void speedhq_init_static_data(void)
{
/* Exactly the same as MPEG-2, except little-endian. */
reverse_code(ff_mpeg12_vlc_dc_lum_code,
ff_mpeg12_vlc_dc_lum_bits,
mpeg12_vlc_dc_lum_code_reversed,
12);
reverse_code(ff_mpeg12_vlc_dc_chroma_code,
ff_mpeg12_vlc_dc_chroma_bits,
mpeg12_vlc_dc_chroma_code_reversed,
12);
ff_rl_init(&ff_rl_speedhq, speedhq_static_rl_table_store);
/* build unified dc encoding tables */