rv34.c

ffmpeg移植到symbian的全部源代码

static void rv34_apply_differences(RV34DecContext *r, int cbp)
{
    static const int shifts[4] = { 0, 2, 8, 10 };
    MpegEncContext *s = &r->s;
    int i;

    for(i = 0; i < 4; i++)
        if(cbp & (LUMA_CBP_BLOCK_MASK << shifts[i]))
            s->dsp.add_pixels_clamped(s->block[i], s->dest[0] + (i & 1)*8 + (i&2)*4*s->linesize, s->linesize);
    if(cbp & U_CBP_MASK)
        s->dsp.add_pixels_clamped(s->block[4], s->dest[1], s->uvlinesize);
    if(cbp & V_CBP_MASK)
        s->dsp.add_pixels_clamped(s->block[5], s->dest[2], s->uvlinesize);
}

static int rv34_decode_macroblock(RV34DecContext *r, int8_t *intra_types)
{
    MpegEncContext *s = &r->s;
    GetBitContext *gb = &s->gb;
    int cbp, cbp2;
    int i, blknum, blkoff;
    DCTELEM block16[64];
    int luma_dc_quant;
    int dist;
    int mb_pos = s->mb_x + s->mb_y * s->mb_stride;

    // Calculate which neighbours are available. Maybe it's worth optimizing too.
    memset(r->avail_cache, 0, sizeof(r->avail_cache));
    fill_rectangle(r->avail_cache + 5, 2, 2, 4, 1, 4);
    dist = (s->mb_x - s->resync_mb_x) + (s->mb_y - s->resync_mb_y) * s->mb_width;
    if(s->mb_x && dist)
        r->avail_cache[4] =
        r->avail_cache[8] = s->current_picture_ptr->mb_type[mb_pos - 1];
    if(dist >= s->mb_width)
        r->avail_cache[1] =
        r->avail_cache[2] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride];
    if(((s->mb_x+1) < s->mb_width) && dist >= s->mb_width - 1)
        r->avail_cache[3] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride + 1];
    if(s->mb_x && dist > s->mb_width)
        r->avail_cache[0] = s->current_picture_ptr->mb_type[mb_pos - s->mb_stride - 1];

    s->qscale = r->si.quant;
    cbp = cbp2 = rv34_decode_mb_header(r, intra_types);
    r->cbp_luma  [s->mb_x + s->mb_y * s->mb_stride] = cbp;
    r->cbp_chroma[s->mb_x + s->mb_y * s->mb_stride] = cbp >> 16;
    s->current_picture.qscale_table[s->mb_x + s->mb_y * s->mb_stride] = s->qscale;

    if(cbp == -1)
        return -1;

    luma_dc_quant = r->si.type ? r->luma_dc_quant_p[s->qscale] : r->luma_dc_quant_i[s->qscale];
    if(r->is16){
        memset(block16, 0, sizeof(block16));
        rv34_decode_block(block16, gb, r->cur_vlcs, 3, 0);
        rv34_dequant4x4_16x16(block16, rv34_qscale_tab[luma_dc_quant],rv34_qscale_tab[s->qscale]);
        rv34_inv_transform_noround(block16);
    }

    for(i = 0; i < 16; i++, cbp >>= 1){
        if(!r->is16 && !(cbp & 1)) continue;
        blknum = ((i & 2) >> 1) + ((i & 8) >> 2);
        blkoff = ((i & 1) << 2) + ((i & 4) << 3);
        if(cbp & 1)
            rv34_decode_block(s->block[blknum] + blkoff, gb, r->cur_vlcs, r->luma_vlc, 0);
        rv34_dequant4x4(s->block[blknum] + blkoff, rv34_qscale_tab[luma_dc_quant],rv34_qscale_tab[s->qscale]);
        if(r->is16) //FIXME: optimize
            s->block[blknum][blkoff] = block16[(i & 3) | ((i & 0xC) << 1)];
        rv34_inv_transform(s->block[blknum] + blkoff);
    }
    if(r->block_type == RV34_MB_P_MIX16x16)
        r->cur_vlcs = choose_vlc_set(r->si.quant, r->si.vlc_set, 1);
    for(; i < 24; i++, cbp >>= 1){
        if(!(cbp & 1)) continue;
        blknum = ((i & 4) >> 2) + 4;
        blkoff = ((i & 1) << 2) + ((i & 2) << 4);
        rv34_decode_block(s->block[blknum] + blkoff, gb, r->cur_vlcs, r->chroma_vlc, 1);
        rv34_dequant4x4(s->block[blknum] + blkoff, rv34_qscale_tab[rv34_chroma_quant[1][s->qscale]],rv34_qscale_tab[rv34_chroma_quant[0][s->qscale]]);
        rv34_inv_transform(s->block[blknum] + blkoff);
    }
    if(IS_INTRA(s->current_picture_ptr->mb_type[s->mb_x + s->mb_y*s->mb_stride]))
        rv34_output_macroblock(r, intra_types, cbp2, r->is16);
    else
        rv34_apply_differences(r, cbp2);

    return 0;
}

static int check_slice_end(RV34DecContext *r, MpegEncContext *s)
{
    int bits;
    if(s->mb_y >= s->mb_height)
        return 1;
    if(!s->mb_num_left)
        return 1;
    if(r->s.mb_skip_run > 1)
        return 0;
    bits = r->bits - get_bits_count(&s->gb);
    if(bits < 0 || (bits < 8 && !show_bits(&s->gb, bits)))
        return 1;
    return 0;
}

static inline int slice_compare(SliceInfo *si1, SliceInfo *si2)
{
    return si1->type   != si2->type  ||
           si1->start  >= si2->start ||
           si1->width  != si2->width ||
           si1->height != si2->height||
           si1->pts    != si2->pts;
}

static int rv34_decode_slice(RV34DecContext *r, int end, uint8_t* buf, int buf_size)
{
    MpegEncContext *s = &r->s;
    GetBitContext *gb = &s->gb;
    int mb_pos;
    int res;

    init_get_bits(&r->s.gb, buf, buf_size*8);
    res = r->parse_slice_header(r, gb, &r->si);
    if(res < 0){
        av_log(s->avctx, AV_LOG_ERROR, "Incorrect or unknown slice header\n");
        return -1;
    }

    if ((s->mb_x == 0 && s->mb_y == 0) || s->current_picture_ptr==NULL) {
        if(s->width != r->si.width || s->height != r->si.height){
            av_log(s->avctx, AV_LOG_DEBUG, "Changing dimensions to %dx%d\n", r->si.width,r->si.height);
            MPV_common_end(s);
            s->width  = r->si.width;
            s->height = r->si.height;
            if(MPV_common_init(s) < 0)
                return -1;
            r->intra_types_hist = av_realloc(r->intra_types_hist, s->b4_stride * 4 * 2 * sizeof(*r->intra_types_hist));
            r->intra_types = r->intra_types_hist + s->b4_stride * 4;
            r->mb_type = av_realloc(r->mb_type, r->s.mb_stride * r->s.mb_height * sizeof(*r->mb_type));
            r->cbp_luma   = av_realloc(r->cbp_luma,   r->s.mb_stride * r->s.mb_height * sizeof(*r->cbp_luma));
            r->cbp_chroma = av_realloc(r->cbp_chroma, r->s.mb_stride * r->s.mb_height * sizeof(*r->cbp_chroma));
        }
        s->pict_type = r->si.type ? r->si.type : FF_I_TYPE;
        if(MPV_frame_start(s, s->avctx) < 0)
            return -1;
        ff_er_frame_start(s);
        s->current_picture_ptr = &s->current_picture;
        r->cur_pts = r->si.pts;
        if(s->pict_type != FF_B_TYPE){
            r->last_pts = r->next_pts;
            r->next_pts = r->cur_pts;
        }
        s->mb_x = s->mb_y = 0;
    }

    r->si.end = end;
    s->qscale = r->si.quant;
    r->bits = buf_size*8;
    s->mb_num_left = r->si.end - r->si.start;
    r->s.mb_skip_run = 0;

    mb_pos = s->mb_x + s->mb_y * s->mb_width;
    if(r->si.start != mb_pos){
        av_log(s->avctx, AV_LOG_ERROR, "Slice indicates MB offset %d, got %d\n", r->si.start, mb_pos);
        s->mb_x = r->si.start % s->mb_width;
        s->mb_y = r->si.start / s->mb_width;
    }
    memset(r->intra_types_hist, -1, s->b4_stride * 4 * 2 * sizeof(*r->intra_types_hist));
    s->first_slice_line = 1;
    s->resync_mb_x= s->mb_x;
    s->resync_mb_y= s->mb_y;

    ff_init_block_index(s);
    while(!check_slice_end(r, s)) {
        ff_update_block_index(s);
        s->dsp.clear_blocks(s->block[0]);

        if(rv34_decode_macroblock(r, r->intra_types + s->mb_x * 4 + 1) < 0){
            ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_ERROR|DC_ERROR|MV_ERROR);
            return -1;
        }
        if (++s->mb_x == s->mb_width) {
            s->mb_x = 0;
            s->mb_y++;
            ff_init_block_index(s);

            memmove(r->intra_types_hist, r->intra_types, s->b4_stride * 4 * sizeof(*r->intra_types_hist));
            memset(r->intra_types, -1, s->b4_stride * 4 * sizeof(*r->intra_types_hist));
        }
        if(s->mb_x == s->resync_mb_x)
            s->first_slice_line=0;
        s->mb_num_left--;
    }
    ff_er_add_slice(s, s->resync_mb_x, s->resync_mb_y, s->mb_x-1, s->mb_y, AC_END|DC_END|MV_END);

    return s->mb_y == s->mb_height;
}

/** @} */ // recons group end

/**
 * Initialize decoder.
 */
av_cold int ff_rv34_decode_init(AVCodecContext *avctx)
{
    RV34DecContext *r = avctx->priv_data;
    MpegEncContext *s = &r->s;

    MPV_decode_defaults(s);
    s->avctx= avctx;
    s->out_format = FMT_H263;
    s->codec_id= avctx->codec_id;

    s->width = avctx->width;
    s->height = avctx->height;

    r->s.avctx = avctx;
    avctx->flags |= CODEC_FLAG_EMU_EDGE;
    r->s.flags |= CODEC_FLAG_EMU_EDGE;
    avctx->pix_fmt = PIX_FMT_YUV420P;
    avctx->has_b_frames = 1;
    s->low_delay = 0;

    if (MPV_common_init(s) < 0)
        return -1;

    ff_h264_pred_init(&r->h, CODEC_ID_RV40);

    r->intra_types_hist = av_malloc(s->b4_stride * 4 * 2 * sizeof(*r->intra_types_hist));
    r->intra_types = r->intra_types_hist + s->b4_stride * 4;

    r->mb_type = av_mallocz(r->s.mb_stride * r->s.mb_height * sizeof(*r->mb_type));

    r->cbp_luma   = av_malloc(r->s.mb_stride * r->s.mb_height * sizeof(*r->cbp_luma));
    r->cbp_chroma = av_malloc(r->s.mb_stride * r->s.mb_height * sizeof(*r->cbp_chroma));

    if(!intra_vlcs[0].cbppattern[0].bits)
        rv34_init_tables();

    return 0;
}

static int get_slice_offset(AVCodecContext *avctx, uint8_t *buf, int n)
{
    if(avctx->slice_count) return avctx->slice_offset[n];
    else                   return AV_RL32(buf + n*8 - 4) == 1 ? AV_RL32(buf + n*8) :  AV_RB32(buf + n*8);
}

int ff_rv34_decode_frame(AVCodecContext *avctx,
                            void *data, int *data_size,
                            uint8_t *buf, int buf_size)
{
    RV34DecContext *r = avctx->priv_data;
    MpegEncContext *s = &r->s;
    AVFrame *pict = data;
    SliceInfo si;
    int i;
    int slice_count;
    uint8_t *slices_hdr = NULL;
    int last = 0;

    /* no supplementary picture */
    if (buf_size == 0) {
        /* special case for last picture */
        if (s->low_delay==0 && s->next_picture_ptr) {
            *pict= *(AVFrame*)s->next_picture_ptr;
            s->next_picture_ptr= NULL;

            *data_size = sizeof(AVFrame);
        }
        return 0;
    }

    if(!avctx->slice_count){
        slice_count = (*buf++) + 1;
        slices_hdr = buf + 4;
        buf += 8 * slice_count;
    }else
        slice_count = avctx->slice_count;

    for(i=0; i<slice_count; i++){
        int offset= get_slice_offset(avctx, slices_hdr, i);
        int size;
        if(i+1 == slice_count)
            size= buf_size - offset;
        else
            size= get_slice_offset(avctx, slices_hdr, i+1) - offset;

        r->si.end = s->mb_width * s->mb_height;
        if(i+1 < slice_count){
            init_get_bits(&s->gb, buf+get_slice_offset(avctx, slices_hdr, i+1), (buf_size-get_slice_offset(avctx, slices_hdr, i+1))*8);
            if(r->parse_slice_header(r, &r->s.gb, &si) < 0){
                if(i+2 < slice_count)
                    size = get_slice_offset(avctx, slices_hdr, i+2) - offset;
                else
                    size = buf_size - offset;
            }else
                r->si.end = si.start;
        }
        last = rv34_decode_slice(r, r->si.end, buf + offset, size);
        s->mb_num_left = r->s.mb_x + r->s.mb_y*r->s.mb_width - r->si.start;
        if(last)
            break;
    }

    if(last){
        if(r->loop_filter)
            r->loop_filter(r);
        ff_er_frame_end(s);
        MPV_frame_end(s);
        if (s->pict_type == FF_B_TYPE || s->low_delay) {
            *pict= *(AVFrame*)s->current_picture_ptr;
        } else if (s->last_picture_ptr != NULL) {
            *pict= *(AVFrame*)s->last_picture_ptr;
        }

        if(s->last_picture_ptr || s->low_delay){
            *data_size = sizeof(AVFrame);
            ff_print_debug_info(s, pict);
        }
        s->current_picture_ptr= NULL; //so we can detect if frame_end wasnt called (find some nicer solution...)
    }
    return buf_size;
}

av_cold int ff_rv34_decode_end(AVCodecContext *avctx)
{
    RV34DecContext *r = avctx->priv_data;

    MPV_common_end(&r->s);

    av_freep(&r->intra_types_hist);
    r->intra_types = NULL;
    av_freep(&r->mb_type);

    return 0;
}