Libav 0.7.1
libavcodec/dxva2_mpeg2.c
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00001 /*
00002  * MPEG-2 HW acceleration.
00003  *
00004  * copyright (c) 2010 Laurent Aimar
00005  *
00006  * This file is part of Libav.
00007  *
00008  * Libav is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * Libav is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with Libav; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00023 #include "dxva2_internal.h"
00024 
00025 #define MAX_SLICES (SLICE_MAX_START_CODE - SLICE_MIN_START_CODE + 1)
00026 struct dxva2_picture_context {
00027     DXVA_PictureParameters pp;
00028     DXVA_QmatrixData       qm;
00029     unsigned               slice_count;
00030     DXVA_SliceInfo         slice[MAX_SLICES];
00031 
00032     const uint8_t          *bitstream;
00033     unsigned               bitstream_size;
00034 };
00035 
00036 static void fill_picture_parameters(AVCodecContext *avctx,
00037                                     struct dxva_context *ctx,
00038                                     const struct MpegEncContext *s,
00039                                     DXVA_PictureParameters *pp)
00040 {
00041     const Picture *current_picture = s->current_picture_ptr;
00042     int is_field = s->picture_structure != PICT_FRAME;
00043 
00044     memset(pp, 0, sizeof(*pp));
00045     pp->wDecodedPictureIndex         = ff_dxva2_get_surface_index(ctx, current_picture);
00046     pp->wDeblockedPictureIndex       = 0;
00047     if (s->pict_type != AV_PICTURE_TYPE_I)
00048         pp->wForwardRefPictureIndex  = ff_dxva2_get_surface_index(ctx, &s->last_picture);
00049     else
00050         pp->wForwardRefPictureIndex  = 0xffff;
00051     if (s->pict_type == AV_PICTURE_TYPE_B)
00052         pp->wBackwardRefPictureIndex = ff_dxva2_get_surface_index(ctx, &s->next_picture);
00053     else
00054         pp->wBackwardRefPictureIndex = 0xffff;
00055     pp->wPicWidthInMBminus1          = s->mb_width  - 1;
00056     pp->wPicHeightInMBminus1         = (s->mb_height >> is_field) - 1;
00057     pp->bMacroblockWidthMinus1       = 15;
00058     pp->bMacroblockHeightMinus1      = 15;
00059     pp->bBlockWidthMinus1            = 7;
00060     pp->bBlockHeightMinus1           = 7;
00061     pp->bBPPminus1                   = 7;
00062     pp->bPicStructure                = s->picture_structure;
00063     pp->bSecondField                 = is_field && !s->first_field;
00064     pp->bPicIntra                    = s->pict_type == AV_PICTURE_TYPE_I;
00065     pp->bPicBackwardPrediction       = s->pict_type == AV_PICTURE_TYPE_B;
00066     pp->bBidirectionalAveragingMode  = 0;
00067     pp->bMVprecisionAndChromaRelation= 0; /* FIXME */
00068     pp->bChromaFormat                = s->chroma_format;
00069     pp->bPicScanFixed                = 1;
00070     pp->bPicScanMethod               = s->alternate_scan ? 1 : 0;
00071     pp->bPicReadbackRequests         = 0;
00072     pp->bRcontrol                    = 0;
00073     pp->bPicSpatialResid8            = 0;
00074     pp->bPicOverflowBlocks           = 0;
00075     pp->bPicExtrapolation            = 0;
00076     pp->bPicDeblocked                = 0;
00077     pp->bPicDeblockConfined          = 0;
00078     pp->bPic4MVallowed               = 0;
00079     pp->bPicOBMC                     = 0;
00080     pp->bPicBinPB                    = 0;
00081     pp->bMV_RPS                      = 0;
00082     pp->bReservedBits                = 0;
00083     pp->wBitstreamFcodes             = (s->mpeg_f_code[0][0] << 12) |
00084                                        (s->mpeg_f_code[0][1] <<  8) |
00085                                        (s->mpeg_f_code[1][0] <<  4) |
00086                                        (s->mpeg_f_code[1][1]      );
00087     pp->wBitstreamPCEelements        = (s->intra_dc_precision         << 14) |
00088                                        (s->picture_structure          << 12) |
00089                                        (s->top_field_first            << 11) |
00090                                        (s->frame_pred_frame_dct       << 10) |
00091                                        (s->concealment_motion_vectors <<  9) |
00092                                        (s->q_scale_type               <<  8) |
00093                                        (s->intra_vlc_format           <<  7) |
00094                                        (s->alternate_scan             <<  6) |
00095                                        (s->repeat_first_field         <<  5) |
00096                                        (s->chroma_420_type            <<  4) |
00097                                        (s->progressive_frame          <<  3);
00098     pp->bBitstreamConcealmentNeed    = 0;
00099     pp->bBitstreamConcealmentMethod  = 0;
00100 }
00101 
00102 static void fill_quantization_matrices(AVCodecContext *avctx,
00103                                        struct dxva_context *ctx,
00104                                        const struct MpegEncContext *s,
00105                                        DXVA_QmatrixData *qm)
00106 {
00107     int i;
00108     for (i = 0; i < 4; i++)
00109         qm->bNewQmatrix[i] = 1;
00110     for (i = 0; i < 64; i++) {
00111         int n = s->dsp.idct_permutation[ff_zigzag_direct[i]];
00112         qm->Qmatrix[0][i] = s->intra_matrix[n];;
00113         qm->Qmatrix[1][i] = s->inter_matrix[n];;
00114         qm->Qmatrix[2][i] = s->chroma_intra_matrix[n];;
00115         qm->Qmatrix[3][i] = s->chroma_inter_matrix[n];;
00116     }
00117 }
00118 
00119 static void fill_slice(AVCodecContext *avctx,
00120                        const struct MpegEncContext *s,
00121                        DXVA_SliceInfo *slice,
00122                        unsigned position,
00123                        const uint8_t *buffer, unsigned size)
00124 {
00125     int is_field = s->picture_structure != PICT_FRAME;
00126     GetBitContext gb;
00127 
00128     memset(slice, 0, sizeof(*slice));
00129     slice->wHorizontalPosition = s->mb_x;
00130     slice->wVerticalPosition   = s->mb_y >> is_field;
00131     slice->dwSliceBitsInBuffer = 8 * size;
00132     slice->dwSliceDataLocation = position;
00133     slice->bStartCodeBitOffset = 0;
00134     slice->bReservedBits       = 0;
00135     /* XXX We store the index of the first MB and it will be fixed later */
00136     slice->wNumberMBsInSlice   = (s->mb_y >> is_field) * s->mb_width + s->mb_x;
00137     slice->wBadSliceChopping   = 0;
00138 
00139     init_get_bits(&gb, &buffer[4], 8 * (size - 4));
00140 
00141     slice->wQuantizerScaleCode = get_bits(&gb, 5);
00142     while (get_bits1(&gb))
00143         skip_bits(&gb, 8);
00144 
00145     slice->wMBbitOffset        = 4 * 8 + get_bits_count(&gb);
00146 }
00147 static int commit_bitstream_and_slice_buffer(AVCodecContext *avctx,
00148                                              DXVA2_DecodeBufferDesc *bs,
00149                                              DXVA2_DecodeBufferDesc *sc)
00150 {
00151     const struct MpegEncContext *s = avctx->priv_data;
00152     struct dxva_context *ctx = avctx->hwaccel_context;
00153     struct dxva2_picture_context *ctx_pic =
00154         s->current_picture_ptr->hwaccel_picture_private;
00155     const int is_field = s->picture_structure != PICT_FRAME;
00156     const unsigned mb_count = s->mb_width * (s->mb_height >> is_field);
00157     uint8_t  *dxva_data, *current, *end;
00158     unsigned dxva_size;
00159     unsigned i;
00160 
00161     if (FAILED(IDirectXVideoDecoder_GetBuffer(ctx->decoder,
00162                                               DXVA2_BitStreamDateBufferType,
00163                                               &dxva_data, &dxva_size)))
00164         return -1;
00165     current = dxva_data;
00166     end = dxva_data + dxva_size;
00167 
00168     for (i = 0; i < ctx_pic->slice_count; i++) {
00169         DXVA_SliceInfo *slice = &ctx_pic->slice[i];
00170         unsigned position = slice->dwSliceDataLocation;
00171         unsigned size     = slice->dwSliceBitsInBuffer / 8;
00172         if (size > end - current) {
00173             av_log(avctx, AV_LOG_ERROR, "Failed to build bitstream");
00174             break;
00175         }
00176         slice->dwSliceDataLocation = current - dxva_data;
00177 
00178         if (i < ctx_pic->slice_count - 1)
00179             slice->wNumberMBsInSlice =
00180                 slice[1].wNumberMBsInSlice - slice[0].wNumberMBsInSlice;
00181         else
00182             slice->wNumberMBsInSlice =
00183                 mb_count - slice[0].wNumberMBsInSlice;
00184 
00185         memcpy(current, &ctx_pic->bitstream[position], size);
00186         current += size;
00187     }
00188     if (FAILED(IDirectXVideoDecoder_ReleaseBuffer(ctx->decoder,
00189                                                   DXVA2_BitStreamDateBufferType)))
00190         return -1;
00191     if (i < ctx_pic->slice_count)
00192         return -1;
00193 
00194     memset(bs, 0, sizeof(*bs));
00195     bs->CompressedBufferType = DXVA2_BitStreamDateBufferType;
00196     bs->DataSize             = current - dxva_data;
00197     bs->NumMBsInBuffer       = mb_count;
00198 
00199     return ff_dxva2_commit_buffer(avctx, ctx, sc,
00200                                   DXVA2_SliceControlBufferType,
00201                                   ctx_pic->slice,
00202                                   ctx_pic->slice_count * sizeof(*ctx_pic->slice),
00203                                   mb_count);
00204 }
00205 
00206 static int start_frame(AVCodecContext *avctx,
00207                        av_unused const uint8_t *buffer,
00208                        av_unused uint32_t size)
00209 {
00210     const struct MpegEncContext *s = avctx->priv_data;
00211     struct dxva_context *ctx = avctx->hwaccel_context;
00212     struct dxva2_picture_context *ctx_pic =
00213         s->current_picture_ptr->hwaccel_picture_private;
00214 
00215     if (!ctx->decoder || !ctx->cfg || ctx->surface_count <= 0)
00216         return -1;
00217     assert(ctx_pic);
00218 
00219     fill_picture_parameters(avctx, ctx, s, &ctx_pic->pp);
00220     fill_quantization_matrices(avctx, ctx, s, &ctx_pic->qm);
00221 
00222     ctx_pic->slice_count    = 0;
00223     ctx_pic->bitstream_size = 0;
00224     ctx_pic->bitstream      = NULL;
00225     return 0;
00226 }
00227 
00228 static int decode_slice(AVCodecContext *avctx,
00229                         const uint8_t *buffer, uint32_t size)
00230 {
00231     const struct MpegEncContext *s = avctx->priv_data;
00232     struct dxva2_picture_context *ctx_pic =
00233         s->current_picture_ptr->hwaccel_picture_private;
00234     unsigned position;
00235 
00236     if (ctx_pic->slice_count >= MAX_SLICES)
00237         return -1;
00238 
00239     if (!ctx_pic->bitstream)
00240         ctx_pic->bitstream = buffer;
00241     ctx_pic->bitstream_size += size;
00242 
00243     position = buffer - ctx_pic->bitstream;
00244     fill_slice(avctx, s, &ctx_pic->slice[ctx_pic->slice_count++], position,
00245                buffer, size);
00246     return 0;
00247 }
00248 
00249 static int end_frame(AVCodecContext *avctx)
00250 {
00251     struct MpegEncContext *s = avctx->priv_data;
00252     struct dxva2_picture_context *ctx_pic =
00253         s->current_picture_ptr->hwaccel_picture_private;
00254 
00255     if (ctx_pic->slice_count <= 0 || ctx_pic->bitstream_size <= 0)
00256         return -1;
00257     return ff_dxva2_common_end_frame(avctx, s,
00258                                      &ctx_pic->pp, sizeof(ctx_pic->pp),
00259                                      &ctx_pic->qm, sizeof(ctx_pic->qm),
00260                                      commit_bitstream_and_slice_buffer);
00261 }
00262 
00263 AVHWAccel ff_mpeg2_dxva2_hwaccel = {
00264     .name           = "mpeg2_dxva2",
00265     .type           = AVMEDIA_TYPE_VIDEO,
00266     .id             = CODEC_ID_MPEG2VIDEO,
00267     .pix_fmt        = PIX_FMT_DXVA2_VLD,
00268     .capabilities   = 0,
00269     .start_frame    = start_frame,
00270     .decode_slice   = decode_slice,
00271     .end_frame      = end_frame,
00272     .priv_data_size = sizeof(struct dxva2_picture_context),
00273 };
00274