| 1 | /* |
| 2 | * Mpeg video formats-related defines and utility functions |
| 3 | * |
| 4 | * This file is part of FFmpeg. |
| 5 | * |
| 6 | * FFmpeg is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * FFmpeg is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with FFmpeg; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #include <stdint.h> |
| 22 | |
| 23 | #include "libavutil/common.h" |
| 24 | #include "libavutil/frame.h" |
| 25 | #include "libavutil/pixdesc.h" |
| 26 | |
| 27 | #include "avcodec.h" |
| 28 | #include "mpegutils.h" |
| 29 | |
| 30 | void ff_draw_horiz_band(AVCodecContext *avctx, |
| 31 | AVFrame *cur, AVFrame *last, |
| 32 | int y, int h, int picture_structure, |
| 33 | int first_field, int low_delay) |
| 34 | { |
| 35 | const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt); |
| 36 | int vshift = desc->log2_chroma_h; |
| 37 | const int field_pic = picture_structure != PICT_FRAME; |
| 38 | if (field_pic) { |
| 39 | h <<= 1; |
| 40 | y <<= 1; |
| 41 | } |
| 42 | |
| 43 | h = FFMIN(h, avctx->height - y); |
| 44 | |
| 45 | if (field_pic && first_field && |
| 46 | !(avctx->slice_flags & SLICE_FLAG_ALLOW_FIELD)) |
| 47 | return; |
| 48 | |
| 49 | if (avctx->draw_horiz_band) { |
| 50 | AVFrame *src; |
| 51 | int offset[AV_NUM_DATA_POINTERS]; |
| 52 | int i; |
| 53 | |
| 54 | if (cur->pict_type == AV_PICTURE_TYPE_B || low_delay || |
| 55 | (avctx->slice_flags & SLICE_FLAG_CODED_ORDER)) |
| 56 | src = cur; |
| 57 | else if (last) |
| 58 | src = last; |
| 59 | else |
| 60 | return; |
| 61 | |
| 62 | if (cur->pict_type == AV_PICTURE_TYPE_B && |
| 63 | picture_structure == PICT_FRAME && |
| 64 | avctx->codec_id != AV_CODEC_ID_SVQ3) { |
| 65 | for (i = 0; i < AV_NUM_DATA_POINTERS; i++) |
| 66 | offset[i] = 0; |
| 67 | } else { |
| 68 | offset[0]= y * src->linesize[0]; |
| 69 | offset[1]= |
| 70 | offset[2]= (y >> vshift) * src->linesize[1]; |
| 71 | for (i = 3; i < AV_NUM_DATA_POINTERS; i++) |
| 72 | offset[i] = 0; |
| 73 | } |
| 74 | |
| 75 | emms_c(); |
| 76 | |
| 77 | avctx->draw_horiz_band(avctx, src, offset, |
| 78 | y, picture_structure, h); |
| 79 | } |
| 80 | } |