PeerStreamer

/*

 * MPEG-2 HW acceleration.

 *

 * copyright (c) 2010 Laurent Aimar

 *

 * 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 "dxva2_internal.h"

#define MAX_SLICES (SLICE_MAX_START_CODE - SLICE_MIN_START_CODE + 1)

struct dxva2_picture_context {

    DXVA_PictureParameters pp;

    DXVA_QmatrixData       qm;

    unsigned               slice_count;

    DXVA_SliceInfo         slice[MAX_SLICES];

    const uint8_t          *bitstream;

    unsigned               bitstream_size;

};

static void fill_picture_parameters(AVCodecContext *avctx,

                                    struct dxva_context *ctx,

                                    const struct MpegEncContext *s,

                                    DXVA_PictureParameters *pp)

{

    const Picture *current_picture = s->current_picture_ptr;

    int is_field = s->picture_structure != PICT_FRAME;

    memset(pp, 0, sizeof(*pp));

    pp->wDecodedPictureIndex         = ff_dxva2_get_surface_index(ctx, current_picture);

    pp->wDeblockedPictureIndex       = 0;

    if (s->pict_type != FF_I_TYPE)

        pp->wForwardRefPictureIndex  = ff_dxva2_get_surface_index(ctx, &s->last_picture);

    else

        pp->wForwardRefPictureIndex  = 0xffff;

    if (s->pict_type == FF_B_TYPE)

        pp->wBackwardRefPictureIndex = ff_dxva2_get_surface_index(ctx, &s->next_picture);

    else

        pp->wBackwardRefPictureIndex = 0xffff;

    pp->wPicWidthInMBminus1          = s->mb_width  - 1;

    pp->wPicHeightInMBminus1         = (s->mb_height >> is_field) - 1;

    pp->bMacroblockWidthMinus1       = 15;

    pp->bMacroblockHeightMinus1      = 15;

    pp->bBlockWidthMinus1            = 7;

    pp->bBlockHeightMinus1           = 7;

    pp->bBPPminus1                   = 7;

    pp->bPicStructure                = s->picture_structure;

    pp->bSecondField                 = is_field && !s->first_field;

    pp->bPicIntra                    = s->pict_type == FF_I_TYPE;

    pp->bPicBackwardPrediction       = s->pict_type == FF_B_TYPE;

    pp->bBidirectionalAveragingMode  = 0;

    pp->bMVprecisionAndChromaRelation= 0; /* FIXME */

    pp->bChromaFormat                = s->chroma_format;

    pp->bPicScanFixed                = 1;

    pp->bPicScanMethod               = s->alternate_scan ? 1 : 0;

    pp->bPicReadbackRequests         = 0;

    pp->bRcontrol                    = 0;

    pp->bPicSpatialResid8            = 0;

    pp->bPicOverflowBlocks           = 0;

    pp->bPicExtrapolation            = 0;

    pp->bPicDeblocked                = 0;

    pp->bPicDeblockConfined          = 0;

    pp->bPic4MVallowed               = 0;

    pp->bPicOBMC                     = 0;

    pp->bPicBinPB                    = 0;

    pp->bMV_RPS                      = 0;

    pp->bReservedBits                = 0;

    pp->wBitstreamFcodes             = (s->mpeg_f_code[0][0] << 12) |

                                       (s->mpeg_f_code[0][1] <<  8) |

                                       (s->mpeg_f_code[1][0] <<  4) |

                                       (s->mpeg_f_code[1][1]      );

    pp->wBitstreamPCEelements        = (s->intra_dc_precision         << 14) |

                                       (s->picture_structure          << 12) |

                                       (s->top_field_first            << 11) |

                                       (s->frame_pred_frame_dct       << 10) |

                                       (s->concealment_motion_vectors <<  9) |

                                       (s->q_scale_type               <<  8) |

                                       (s->intra_vlc_format           <<  7) |

                                       (s->alternate_scan             <<  6) |

                                       (s->repeat_first_field         <<  5) |

                                       (s->chroma_420_type            <<  4) |

                                       (s->progressive_frame          <<  3);

    pp->bBitstreamConcealmentNeed    = 0;

    pp->bBitstreamConcealmentMethod  = 0;

}

static void fill_quantization_matrices(AVCodecContext *avctx,

                                       struct dxva_context *ctx,

                                       const struct MpegEncContext *s,

                                       DXVA_QmatrixData *qm)

{

    int i;

    for (i = 0; i < 4; i++)

        qm->bNewQmatrix[i] = 1;

    for (i = 0; i < 64; i++) {

        int n = s->dsp.idct_permutation[ff_zigzag_direct[i]];

        qm->Qmatrix[0][i] = s->intra_matrix[n];;

        qm->Qmatrix[1][i] = s->inter_matrix[n];;

        qm->Qmatrix[2][i] = s->chroma_intra_matrix[n];;

        qm->Qmatrix[3][i] = s->chroma_inter_matrix[n];;

    }

}

static void fill_slice(AVCodecContext *avctx,

                       const struct MpegEncContext *s,

                       DXVA_SliceInfo *slice,

                       unsigned position,

                       const uint8_t *buffer, unsigned size)

{

    int is_field = s->picture_structure != PICT_FRAME;

    GetBitContext gb;

    memset(slice, 0, sizeof(*slice));

    slice->wHorizontalPosition = s->mb_x;

    slice->wVerticalPosition   = s->mb_y >> is_field;

    slice->dwSliceBitsInBuffer = 8 * size;

    slice->dwSliceDataLocation = position;

    slice->bStartCodeBitOffset = 0;

    slice->bReservedBits       = 0;

    /* XXX We store the index of the first MB and it will be fixed later */

    slice->wNumberMBsInSlice   = (s->mb_y >> is_field) * s->mb_width + s->mb_x;

    slice->wBadSliceChopping   = 0;

    init_get_bits(&gb, &buffer[4], 8 * (size - 4));

    slice->wQuantizerScaleCode = get_bits(&gb, 5);

    while (get_bits1(&gb))

        skip_bits(&gb, 8);

    slice->wMBbitOffset        = 4 * 8 + get_bits_count(&gb);

}

static int commit_bitstream_and_slice_buffer(AVCodecContext *avctx,

                                             DXVA2_DecodeBufferDesc *bs,

                                             DXVA2_DecodeBufferDesc *sc)

{

    const struct MpegEncContext *s = avctx->priv_data;

    struct dxva_context *ctx = avctx->hwaccel_context;

    struct dxva2_picture_context *ctx_pic =

        s->current_picture_ptr->hwaccel_picture_private;

    const int is_field = s->picture_structure != PICT_FRAME;

    const unsigned mb_count = s->mb_width * (s->mb_height >> is_field);

    uint8_t  *dxva_data, *current, *end;

    unsigned dxva_size;

    unsigned i;

    if (FAILED(IDirectXVideoDecoder_GetBuffer(ctx->decoder,

                                              DXVA2_BitStreamDateBufferType,

                                              &dxva_data, &dxva_size)))

        return -1;

    current = dxva_data;

    end = dxva_data + dxva_size;

    for (i = 0; i < ctx_pic->slice_count; i++) {

        DXVA_SliceInfo *slice = &ctx_pic->slice[i];

        unsigned position = slice->dwSliceDataLocation;

        unsigned size     = slice->dwSliceBitsInBuffer / 8;

        if (size > end - current) {

            av_log(avctx, AV_LOG_ERROR, "Failed to build bitstream");

            break;

        }

        slice->dwSliceDataLocation = current - dxva_data;

        if (i < ctx_pic->slice_count - 1)

            slice->wNumberMBsInSlice =

                slice[1].wNumberMBsInSlice - slice[0].wNumberMBsInSlice;

        else

            slice->wNumberMBsInSlice =

                mb_count - slice[0].wNumberMBsInSlice;

        memcpy(current, &ctx_pic->bitstream[position], size);

        current += size;

    }

    if (FAILED(IDirectXVideoDecoder_ReleaseBuffer(ctx->decoder,

                                                  DXVA2_BitStreamDateBufferType)))

        return -1;

    if (i < ctx_pic->slice_count)

        return -1;

    memset(bs, 0, sizeof(*bs));

    bs->CompressedBufferType = DXVA2_BitStreamDateBufferType;

    bs->DataSize             = current - dxva_data;

    bs->NumMBsInBuffer       = mb_count;

    return ff_dxva2_commit_buffer(avctx, ctx, sc,

                                  DXVA2_SliceControlBufferType,

                                  ctx_pic->slice,

                                  ctx_pic->slice_count * sizeof(*ctx_pic->slice),

                                  mb_count);

}

static int start_frame(AVCodecContext *avctx,

                       av_unused const uint8_t *buffer,

                       av_unused uint32_t size)

{

    const struct MpegEncContext *s = avctx->priv_data;

    struct dxva_context *ctx = avctx->hwaccel_context;

    struct dxva2_picture_context *ctx_pic =

        s->current_picture_ptr->hwaccel_picture_private;

    if (!ctx->decoder || !ctx->cfg || ctx->surface_count <= 0)

        return -1;

    assert(ctx_pic);

    fill_picture_parameters(avctx, ctx, s, &ctx_pic->pp);

    fill_quantization_matrices(avctx, ctx, s, &ctx_pic->qm);

    ctx_pic->slice_count    = 0;

    ctx_pic->bitstream_size = 0;

    ctx_pic->bitstream      = NULL;

    return 0;

}

static int decode_slice(AVCodecContext *avctx,

                        const uint8_t *buffer, uint32_t size)

{

    const struct MpegEncContext *s = avctx->priv_data;

    struct dxva2_picture_context *ctx_pic =

        s->current_picture_ptr->hwaccel_picture_private;

    unsigned position;

    if (ctx_pic->slice_count >= MAX_SLICES)

        return -1;

    if (!ctx_pic->bitstream)

        ctx_pic->bitstream = buffer;

    ctx_pic->bitstream_size += size;

    position = buffer - ctx_pic->bitstream;

    fill_slice(avctx, s, &ctx_pic->slice[ctx_pic->slice_count++], position,

               buffer, size);

    return 0;

}

static int end_frame(AVCodecContext *avctx)

{

    struct MpegEncContext *s = avctx->priv_data;

    struct dxva2_picture_context *ctx_pic =

        s->current_picture_ptr->hwaccel_picture_private;

    if (ctx_pic->slice_count <= 0 || ctx_pic->bitstream_size <= 0)

        return -1;

    return ff_dxva2_common_end_frame(avctx, s,

                                     &ctx_pic->pp, sizeof(ctx_pic->pp),

                                     &ctx_pic->qm, sizeof(ctx_pic->qm),

                                     commit_bitstream_and_slice_buffer);

}

AVHWAccel ff_mpeg2_dxva2_hwaccel = {

    .name           = "mpeg2_dxva2",

    .type           = AVMEDIA_TYPE_VIDEO,

    .id             = CODEC_ID_MPEG2VIDEO,

    .pix_fmt        = PIX_FMT_DXVA2_VLD,

    .capabilities   = 0,

    .start_frame    = start_frame,

    .decode_slice   = decode_slice,

    .end_frame      = end_frame,

    .priv_data_size = sizeof(struct dxva2_picture_context),

};