PeerStreamer

/*

 * Alpha optimized DSP utils

 * Copyright (c) 2002 Falk Hueffner <falk@debian.org>

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include "asm.h"

#include "dsputil.h"

#include "mpegvideo.h"

static void dct_unquantize_h263_intra_axp(MpegEncContext *s, DCTELEM *block,

                                    int n, int qscale)

{

    int i, n_coeffs;

    uint64_t qmul, qadd;

    uint64_t correction;

    DCTELEM *orig_block = block;

    DCTELEM block0;             /* might not be used uninitialized */

    qadd = WORD_VEC((qscale - 1) | 1);

    qmul = qscale << 1;

    /* This mask kills spill from negative subwords to the next subword.  */

    correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */

    if (!s->h263_aic) {

        if (n < 4)

            block0 = block[0] * s->y_dc_scale;

        else

            block0 = block[0] * s->c_dc_scale;

    } else {

        qadd = 0;

    }

    n_coeffs = 63; // does not always use zigzag table

    for(i = 0; i <= n_coeffs; block += 4, i += 4) {

        uint64_t levels, negmask, zeros, add;

        levels = ldq(block);

        if (levels == 0)

            continue;

#ifdef __alpha_max__

        /* I don't think the speed difference justifies runtime

           detection.  */

        negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */

        negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */

#else

        negmask = cmpbge(WORD_VEC(0x7fff), levels);

        negmask &= (negmask >> 1) | (1 << 7);

        negmask = zap(-1, negmask);

#endif

        zeros = cmpbge(0, levels);

        zeros &= zeros >> 1;

        /* zeros |= zeros << 1 is not needed since qadd <= 255, so

           zapping the lower byte suffices.  */

        levels *= qmul;

        levels -= correction & (negmask << 16);

        /* Negate qadd for negative levels.  */

        add = qadd ^ negmask;

        add += WORD_VEC(0x0001) & negmask;

        /* Set qadd to 0 for levels == 0.  */

        add = zap(add, zeros);

        levels += add;

        stq(levels, block);

    }

    if (s->mb_intra && !s->h263_aic)

        orig_block[0] = block0;

}

static void dct_unquantize_h263_inter_axp(MpegEncContext *s, DCTELEM *block,

                                    int n, int qscale)

{

    int i, n_coeffs;

    uint64_t qmul, qadd;

    uint64_t correction;

    qadd = WORD_VEC((qscale - 1) | 1);

    qmul = qscale << 1;

    /* This mask kills spill from negative subwords to the next subword.  */

    correction = WORD_VEC((qmul - 1) + 1); /* multiplication / addition */

    n_coeffs = s->intra_scantable.raster_end[s->block_last_index[n]];

    for(i = 0; i <= n_coeffs; block += 4, i += 4) {

        uint64_t levels, negmask, zeros, add;

        levels = ldq(block);

        if (levels == 0)

            continue;

#ifdef __alpha_max__

        /* I don't think the speed difference justifies runtime

           detection.  */

        negmask = maxsw4(levels, -1); /* negative -> ffff (-1) */

        negmask = minsw4(negmask, 0); /* positive -> 0000 (0) */

#else

        negmask = cmpbge(WORD_VEC(0x7fff), levels);

        negmask &= (negmask >> 1) | (1 << 7);

        negmask = zap(-1, negmask);

#endif

        zeros = cmpbge(0, levels);

        zeros &= zeros >> 1;

        /* zeros |= zeros << 1 is not needed since qadd <= 255, so

           zapping the lower byte suffices.  */

        levels *= qmul;

        levels -= correction & (negmask << 16);

        /* Negate qadd for negative levels.  */

        add = qadd ^ negmask;

        add += WORD_VEC(0x0001) & negmask;

        /* Set qadd to 0 for levels == 0.  */

        add = zap(add, zeros);

        levels += add;

        stq(levels, block);

    }

}

void MPV_common_init_axp(MpegEncContext *s)

{

    s->dct_unquantize_h263_intra = dct_unquantize_h263_intra_axp;

    s->dct_unquantize_h263_inter = dct_unquantize_h263_inter_axp;

}