Function vaapi_mpeg2_decode_slice

libavcodec/vaapi_mpeg2.c:134–176

}

static int vaapi_mpeg2_decode_slice(AVCodecContext *avctx, const uint8_t *buffer, uint32_t size)
{
    const MpegEncContext *s = avctx->priv_data;
    VAAPIDecodePicture *pic = s->cur_pic.ptr->hwaccel_picture_private;
    VASliceParameterBufferMPEG2 slice_param;
    GetBitContext gb;
    uint32_t quantiser_scale_code, intra_slice_flag, macroblock_offset;
    int err;

    /* Determine macroblock_offset */
    init_get_bits(&gb, buffer, 8 * size);
    if (get_bits_long(&gb, 32) >> 8 != 1) /* start code */
        return AVERROR_INVALIDDATA;
    quantiser_scale_code = get_bits(&gb, 5);
    intra_slice_flag = get_bits1(&gb);
    if (intra_slice_flag) {
        skip_bits(&gb, 8);
        if (skip_1stop_8data_bits(&gb) < 0)
            return AVERROR_INVALIDDATA;
    }
    macroblock_offset = get_bits_count(&gb);

    slice_param = (VASliceParameterBufferMPEG2) {
        .slice_data_size            = size,
        .slice_data_offset          = 0,
        .slice_data_flag            = VA_SLICE_DATA_FLAG_ALL,
        .macroblock_offset          = macroblock_offset,
        .slice_horizontal_position  = s->mb_x,
        .slice_vertical_position    = s->mb_y >> (s->picture_structure != PICT_FRAME),
        .quantiser_scale_code       = quantiser_scale_code,
        .intra_slice_flag           = intra_slice_flag,
    };

    err = ff_vaapi_decode_make_slice_buffer(avctx, pic,
                                            &slice_param, 1, sizeof(slice_param),
                                            buffer, size);
    if (err < 0) {
        ff_vaapi_decode_cancel(avctx, pic);
        return err;
    }

    return 0;
}

const FFHWAccel ff_mpeg2_vaapi_hwaccel = {
    .p.name               = "mpeg2_vaapi",