transrate.c

来自「VLC媒体播放程序」· C语言 代码 · 共 2,148 行 · 第 1/5 页

        {
            bs_copy( bs, tab->len);
            //dc_diff = UBITS (bs->i_bit_in_cache, size) - UBITS (SBITS (~bs->i_bit_in_cache, 1), size);
            dc_diff = UBITS (bs->i_bit_in_cache, size);
            if (!(dc_diff >> (size - 1))) dc_diff = (dc_diff + 1) - (1 << size);
            bs_copy( bs, size);
            return dc_diff;
        } else
        {
            bs_copy( bs, 2);
            return 0;
        }
    }
    else
    {
        tab = DC_long + (UBITS (bs->i_bit_in_cache, 10) - 0x3e0);
        size = tab->size;
        bs_copy( bs, tab->len + 1);
        //dc_diff = UBITS (bs->i_bit_in_cache, size) - UBITS (SBITS (~bs->i_bit_in_cache, 1), size);
        dc_diff = UBITS (bs->i_bit_in_cache, size);
        if (!(dc_diff >> (size - 1))) dc_diff = (dc_diff + 1) - (1 << size);
        bs_copy( bs, size);
        return dc_diff;
    }
}

static void get_intra_block_B14( bs_transrate_t *bs, const int i_qscale, const int i_qscale_new )
{
    int tst;
    int i, li;
    int val;
    const DCTtab * tab;

    /* Basic sanity check --Meuuh */
    if( i_qscale == 0 )
    {
        return;
    }

    tst = i_qscale_new/i_qscale + ((i_qscale_new%i_qscale) ? 1 : 0);

    li = i = 0;

    for( ;; )
    {
        if (bs->i_bit_in_cache >= 0x28000000)
        {
            tab = DCT_B14AC_5 + (UBITS (bs->i_bit_in_cache, 5) - 5);

            i += tab->run;
            if (i >= 64) break; /* end of block */

    normal_code:
            bs_flush( bs, tab->len );
            val = tab->level;
            if (val >= tst)
            {
                val = (val ^ SBITS (bs->i_bit_in_cache, 1)) - SBITS (bs->i_bit_in_cache, 1);
                putAC( bs, i - li - 1, (val * i_qscale) / i_qscale_new, 0);
                li = i;
            }

            bs_flush( bs, 1 );
            continue;
        }
        else if (bs->i_bit_in_cache >= 0x04000000)
        {
            tab = DCT_B14_8 + (UBITS (bs->i_bit_in_cache, 8) - 4);

            i += tab->run;
            if (i < 64) goto normal_code;

            /* escape code */
            i += (UBITS (bs->i_bit_in_cache, 12) & 0x3F) - 64;
            if (i >= 64) break; /* illegal, check needed to avoid buffer overflow */

            bs_flush( bs, 12 );
            val = SBITS (bs->i_bit_in_cache, 12);
            if (abs(val) >= tst)
            {
                putAC( bs, i - li - 1, (val * i_qscale) / i_qscale_new, 0);
                li = i;
            }

            bs_flush( bs, 12 );

            continue;
        }
        else if (bs->i_bit_in_cache >= 0x02000000)
        {
            tab = DCT_B14_10 + (UBITS (bs->i_bit_in_cache, 10) - 8);
            i += tab->run;
            if (i < 64 ) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00800000)
        {
            tab = DCT_13 + (UBITS (bs->i_bit_in_cache, 13) - 16);
            i += tab->run;
            if (i < 64 ) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00200000)
        {
            tab = DCT_15 + (UBITS (bs->i_bit_in_cache, 15) - 16);
            i += tab->run;
            if (i < 64 ) goto normal_code;
        }
        else
        {
            tab = DCT_16 + UBITS (bs->i_bit_in_cache, 16);
            bs_flush( bs, 16 );
            i += tab->run;
            if (i < 64 ) goto normal_code;
        }
        break;  /* illegal, check needed to avoid buffer overflow */
    }

    bs_copy( bs, 2);    /* end of block code */
}

static void get_intra_block_B15( bs_transrate_t *bs,  const int i_qscale, int const i_qscale_new )
{
    int tst;
    int i, li;
    int val;
    const DCTtab * tab;

    /* Basic sanity check --Meuuh */
    if( i_qscale == 0 )
    {
        return;
    }

    tst = i_qscale_new/i_qscale + ((i_qscale_new%i_qscale) ? 1 : 0);

    li = i = 0;

    for( ;; )
    {
        if (bs->i_bit_in_cache >= 0x04000000)
        {
            tab = DCT_B15_8 + (UBITS (bs->i_bit_in_cache, 8) - 4);

            i += tab->run;
            if (i < 64)
            {
    normal_code:
                bs_flush( bs, tab->len );

                val = tab->level;
                if (val >= tst)
                {
                    val = (val ^ SBITS (bs->i_bit_in_cache, 1)) - SBITS (bs->i_bit_in_cache, 1);
                    putAC( bs, i - li - 1, (val * i_qscale) / i_qscale_new, 1);
                    li = i;
                }

                bs_flush( bs, 1 );
                continue;
            }
            else
            {
                i += (UBITS (bs->i_bit_in_cache, 12) & 0x3F) - 64;

                if (i >= 64) break; /* illegal, check against buffer overflow */

                bs_flush( bs, 12 );
                val = SBITS (bs->i_bit_in_cache, 12);
                if (abs(val) >= tst)
                {
                    putAC( bs, i - li - 1, (val * i_qscale) / i_qscale_new, 1);
                    li = i;
                }

                bs_flush( bs, 12 );
                continue;
            }
        }
        else if (bs->i_bit_in_cache >= 0x02000000)
        {
            tab = DCT_B15_10 + (UBITS (bs->i_bit_in_cache, 10) - 8);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00800000)
        {
            tab = DCT_13 + (UBITS (bs->i_bit_in_cache, 13) - 16);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00200000)
        {
            tab = DCT_15 + (UBITS (bs->i_bit_in_cache, 15) - 16);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else
        {
            tab = DCT_16 + UBITS (bs->i_bit_in_cache, 16);
            bs_flush( bs, 16 );
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        break;  /* illegal, check needed to avoid buffer overflow */
    }

    bs_copy( bs, 4);    /* end of block code */
}


static int get_non_intra_block_drop( transrate_t *tr, RunLevel *blk)
{
    bs_transrate_t *bs = &tr->bs;

    int i, li;
    int val;
    const DCTtab * tab;
    RunLevel *sblk = blk + 1;

    li = i = -1;

    if (bs->i_bit_in_cache >= 0x28000000)
    {
        tab = DCT_B14DC_5 + (UBITS (bs->i_bit_in_cache, 5) - 5);
        goto entry_1;
    }
    else goto entry_2;

    for( ;; )
    {
        if (bs->i_bit_in_cache >= 0x28000000)
        {
            tab = DCT_B14AC_5 + (UBITS (bs->i_bit_in_cache, 5) - 5);

    entry_1:
            i += tab->run;
            if (i >= 64) break; /* end of block */

    normal_code:

            bs_flush( bs, tab->len );
            val = tab->level;
            val = (val ^ SBITS (bs->i_bit_in_cache, 1)) - SBITS (bs->i_bit_in_cache, 1); /* if (bitstream_get (1)) val = -val; */

            blk->level = val;
            blk->run = i - li - 1;
            li = i;
            blk++;

            bs_flush( bs, 1 );
            continue;
        }

    entry_2:

        if (bs->i_bit_in_cache >= 0x04000000)
        {
            tab = DCT_B14_8 + (UBITS (bs->i_bit_in_cache, 8) - 4);

            i += tab->run;
            if (i < 64) goto normal_code;

            /* escape code */

            i += (UBITS (bs->i_bit_in_cache, 12) & 0x3F) - 64;

            if (i >= 64) break; /* illegal, check needed to avoid buffer overflow */

            bs_flush( bs, 12 );
            val = SBITS (bs->i_bit_in_cache, 12);

            blk->level = val;
            blk->run = i - li - 1;
            li = i;
            blk++;

            bs_flush( bs, 12 );
            continue;
        }
        else if (bs->i_bit_in_cache >= 0x02000000)
        {
            tab = DCT_B14_10 + (UBITS (bs->i_bit_in_cache, 10) - 8);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00800000)
        {
            tab = DCT_13 + (UBITS (bs->i_bit_in_cache, 13) - 16);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00200000)
        {
            tab = DCT_15 + (UBITS (bs->i_bit_in_cache, 15) - 16);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else
        {
            tab = DCT_16 + UBITS (bs->i_bit_in_cache, 16);
            bs_flush( bs, 16 );
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        break;  /* illegal, check needed to avoid buffer overflow */
    }
    bs_flush( bs, 2 ); /* dump end of block code */

    // remove last coeff
    if (blk != sblk)
    {
        blk--;
    }

    // remove more coeffs if very late
    if (tr->level_p >= 4 && (blk != sblk))
    {
        blk--;
        if (tr->level_p >= 5 && (blk != sblk))
        {
            blk--;
            if (tr->level_p >= 6 && (blk != sblk))
            {
                blk--;
                if (tr->level_p >= 7 && (blk != sblk))
                    blk--;
            }
        }
    }

    blk->level = 0;

    return i;
}

static int get_non_intra_block_rq( bs_transrate_t *bs, RunLevel *blk,  const int i_qscale, const int i_qscale_new )
{
    int tst;
    int i, li;
    int val;
    const DCTtab * tab;

    /* Basic sanity check --Meuuh */
    if( i_qscale == 0 )
    {
        return 0;
    }

    tst = i_qscale_new/i_qscale + ((i_qscale_new%i_qscale) ? 1 : 0);

    li = i = -1;

    if (bs->i_bit_in_cache >= 0x28000000)
    {
        tab = DCT_B14DC_5 + (UBITS (bs->i_bit_in_cache, 5) - 5);
        goto entry_1;
    }
    else goto entry_2;

    for( ;; )
    {
        if (bs->i_bit_in_cache >= 0x28000000)
        {
            tab = DCT_B14AC_5 + (UBITS (bs->i_bit_in_cache, 5) - 5);

    entry_1:
            i += tab->run;
            if (i >= 64)
            break;  /* end of block */

    normal_code:

            bs_flush( bs, tab->len );
            val = tab->level;
            if (val >= tst)
            {
                val = (val ^ SBITS (bs->i_bit_in_cache, 1)) - SBITS (bs->i_bit_in_cache, 1);
                blk->level = (val * i_qscale) / i_qscale_new;
                blk->run = i - li - 1;
                li = i;
                blk++;
            }

            //if ( ((val) && (tab->level < tst)) || ((!val) && (tab->level >= tst)) )
            //  LOGF("level: %i val: %i tst : %i q: %i nq : %i\n", tab->level, val, tst, q, nq);

            bs_flush( bs, 1 );
            continue;
        }

    entry_2:
        if (bs->i_bit_in_cache >= 0x04000000)
        {
            tab = DCT_B14_8 + (UBITS (bs->i_bit_in_cache, 8) - 4);

            i += tab->run;
            if (i < 64) goto normal_code;

            /* escape code */

            i += (UBITS (bs->i_bit_in_cache, 12) & 0x3F) - 64;

            if (i >= 64) break; /* illegal, check needed to avoid buffer overflow */

            bs_flush( bs, 12 );
            val = SBITS (bs->i_bit_in_cache, 12);
            if (abs(val) >= tst)
            {
                blk->level = (val * i_qscale) / i_qscale_new;
                blk->run = i - li - 1;
                li = i;
                blk++;
            }

            bs_flush( bs, 12 );
            continue;
        }
        else if (bs->i_bit_in_cache >= 0x02000000)
        {
            tab = DCT_B14_10 + (UBITS (bs->i_bit_in_cache, 10) - 8);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00800000)
        {
            tab = DCT_13 + (UBITS (bs->i_bit_in_cache, 13) - 16);
            i += tab->run;
            if (i < 64) goto normal_code;
        }
        else if (bs->i_bit_in_cache >= 0x00200000)
        {