| 1 | /* |
| 2 | * Copyright (c) 2007 Bobby Bingham |
| 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 | /** |
| 22 | * @file |
| 23 | * video vertical flip filter |
| 24 | */ |
| 25 | |
| 26 | #include "libavutil/internal.h" |
| 27 | #include "libavutil/pixdesc.h" |
| 28 | #include "avfilter.h" |
| 29 | #include "internal.h" |
| 30 | #include "video.h" |
| 31 | |
| 32 | typedef struct FlipContext { |
| 33 | int vsub; ///< vertical chroma subsampling |
| 34 | } FlipContext; |
| 35 | |
| 36 | static int config_input(AVFilterLink *link) |
| 37 | { |
| 38 | FlipContext *flip = link->dst->priv; |
| 39 | const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format); |
| 40 | |
| 41 | flip->vsub = desc->log2_chroma_h; |
| 42 | |
| 43 | return 0; |
| 44 | } |
| 45 | |
| 46 | static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h) |
| 47 | { |
| 48 | FlipContext *flip = link->dst->priv; |
| 49 | AVFrame *frame; |
| 50 | int i; |
| 51 | |
| 52 | frame = ff_get_video_buffer(link->dst->outputs[0], w, h); |
| 53 | if (!frame) |
| 54 | return NULL; |
| 55 | |
| 56 | for (i = 0; i < 4; i ++) { |
| 57 | int vsub = i == 1 || i == 2 ? flip->vsub : 0; |
| 58 | int height = FF_CEIL_RSHIFT(h, vsub); |
| 59 | |
| 60 | if (frame->data[i]) { |
| 61 | frame->data[i] += (height - 1) * frame->linesize[i]; |
| 62 | frame->linesize[i] = -frame->linesize[i]; |
| 63 | } |
| 64 | } |
| 65 | |
| 66 | return frame; |
| 67 | } |
| 68 | |
| 69 | static int filter_frame(AVFilterLink *link, AVFrame *frame) |
| 70 | { |
| 71 | FlipContext *flip = link->dst->priv; |
| 72 | int i; |
| 73 | |
| 74 | for (i = 0; i < 4; i ++) { |
| 75 | int vsub = i == 1 || i == 2 ? flip->vsub : 0; |
| 76 | int height = FF_CEIL_RSHIFT(link->h, vsub); |
| 77 | |
| 78 | if (frame->data[i]) { |
| 79 | frame->data[i] += (height - 1) * frame->linesize[i]; |
| 80 | frame->linesize[i] = -frame->linesize[i]; |
| 81 | } |
| 82 | } |
| 83 | |
| 84 | return ff_filter_frame(link->dst->outputs[0], frame); |
| 85 | } |
| 86 | static const AVFilterPad avfilter_vf_vflip_inputs[] = { |
| 87 | { |
| 88 | .name = "default", |
| 89 | .type = AVMEDIA_TYPE_VIDEO, |
| 90 | .get_video_buffer = get_video_buffer, |
| 91 | .filter_frame = filter_frame, |
| 92 | .config_props = config_input, |
| 93 | }, |
| 94 | { NULL } |
| 95 | }; |
| 96 | |
| 97 | static const AVFilterPad avfilter_vf_vflip_outputs[] = { |
| 98 | { |
| 99 | .name = "default", |
| 100 | .type = AVMEDIA_TYPE_VIDEO, |
| 101 | }, |
| 102 | { NULL } |
| 103 | }; |
| 104 | |
| 105 | AVFilter ff_vf_vflip = { |
| 106 | .name = "vflip", |
| 107 | .description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."), |
| 108 | .priv_size = sizeof(FlipContext), |
| 109 | .inputs = avfilter_vf_vflip_inputs, |
| 110 | .outputs = avfilter_vf_vflip_outputs, |
| 111 | }; |