yading@11: /*
yading@11:  * Copyright (c) 2007 Bobby Bingham
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: /**
yading@11:  * @file
yading@11:  * video vertical flip filter
yading@11:  */
yading@11: 
yading@11: #include "libavutil/internal.h"
yading@11: #include "libavutil/pixdesc.h"
yading@11: #include "avfilter.h"
yading@11: #include "internal.h"
yading@11: #include "video.h"
yading@11: 
yading@11: typedef struct {
yading@11:     int vsub;   ///< vertical chroma subsampling
yading@11: } FlipContext;
yading@11: 
yading@11: static int config_input(AVFilterLink *link)
yading@11: {
yading@11:     FlipContext *flip = link->dst->priv;
yading@11:     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
yading@11: 
yading@11:     flip->vsub = desc->log2_chroma_h;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static AVFrame *get_video_buffer(AVFilterLink *link, int w, int h)
yading@11: {
yading@11:     FlipContext *flip = link->dst->priv;
yading@11:     AVFrame *frame;
yading@11:     int i;
yading@11: 
yading@11:     frame = ff_get_video_buffer(link->dst->outputs[0], w, h);
yading@11:     if (!frame)
yading@11:         return NULL;
yading@11: 
yading@11:     for (i = 0; i < 4; i ++) {
yading@11:         int vsub = i == 1 || i == 2 ? flip->vsub : 0;
yading@11: 
yading@11:         if (frame->data[i]) {
yading@11:             frame->data[i] += (((h + (1<<vsub) - 1) >> vsub) - 1) * frame->linesize[i];
yading@11:             frame->linesize[i] = -frame->linesize[i];
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return frame;
yading@11: }
yading@11: 
yading@11: static int filter_frame(AVFilterLink *link, AVFrame *frame)
yading@11: {
yading@11:     FlipContext *flip = link->dst->priv;
yading@11:     int i;
yading@11: 
yading@11:     for (i = 0; i < 4; i ++) {
yading@11:         int vsub = i == 1 || i == 2 ? flip->vsub : 0;
yading@11: 
yading@11:         if (frame->data[i]) {
yading@11:             frame->data[i] += (((link->h + (1<<vsub)-1)>> vsub)-1) * frame->linesize[i];
yading@11:             frame->linesize[i] = -frame->linesize[i];
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return ff_filter_frame(link->dst->outputs[0], frame);
yading@11: }
yading@11: static const AVFilterPad avfilter_vf_vflip_inputs[] = {
yading@11:     {
yading@11:         .name             = "default",
yading@11:         .type             = AVMEDIA_TYPE_VIDEO,
yading@11:         .get_video_buffer = get_video_buffer,
yading@11:         .filter_frame     = filter_frame,
yading@11:         .config_props     = config_input,
yading@11:     },
yading@11:     { NULL }
yading@11: };
yading@11: 
yading@11: static const AVFilterPad avfilter_vf_vflip_outputs[] = {
yading@11:     {
yading@11:         .name = "default",
yading@11:         .type = AVMEDIA_TYPE_VIDEO,
yading@11:     },
yading@11:     { NULL }
yading@11: };
yading@11: 
yading@11: AVFilter avfilter_vf_vflip = {
yading@11:     .name      = "vflip",
yading@11:     .description = NULL_IF_CONFIG_SMALL("Flip the input video vertically."),
yading@11: 
yading@11:     .priv_size = sizeof(FlipContext),
yading@11: 
yading@11:     .inputs    = avfilter_vf_vflip_inputs,
yading@11:     .outputs   = avfilter_vf_vflip_outputs,
yading@11: };