Libav 0.7.1
libavfilter/vf_hflip.c
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00001 /*
00002  * Copyright (c) 2007 Benoit Fouet
00003  * Copyright (c) 2010 Stefano Sabatini
00004  *
00005  * This file is part of Libav.
00006  *
00007  * Libav is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * Libav is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with Libav; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #include "avfilter.h"
00028 #include "libavutil/pixdesc.h"
00029 #include "libavutil/intreadwrite.h"
00030 #include "libavutil/imgutils.h"
00031 
00032 typedef struct {
00033     int max_step[4];    
00034     int hsub, vsub;     
00035 } FlipContext;
00036 
00037 static int query_formats(AVFilterContext *ctx)
00038 {
00039     static const enum PixelFormat pix_fmts[] = {
00040         PIX_FMT_RGB48BE,      PIX_FMT_RGB48LE,
00041         PIX_FMT_BGR48BE,      PIX_FMT_BGR48LE,
00042         PIX_FMT_ARGB,         PIX_FMT_RGBA,
00043         PIX_FMT_ABGR,         PIX_FMT_BGRA,
00044         PIX_FMT_RGB24,        PIX_FMT_BGR24,
00045         PIX_FMT_RGB565BE,     PIX_FMT_RGB565LE,
00046         PIX_FMT_RGB555BE,     PIX_FMT_RGB555LE,
00047         PIX_FMT_BGR565BE,     PIX_FMT_BGR565LE,
00048         PIX_FMT_BGR555BE,     PIX_FMT_BGR555LE,
00049         PIX_FMT_GRAY16BE,     PIX_FMT_GRAY16LE,
00050         PIX_FMT_YUV420P16LE,  PIX_FMT_YUV420P16BE,
00051         PIX_FMT_YUV422P16LE,  PIX_FMT_YUV422P16BE,
00052         PIX_FMT_YUV444P16LE,  PIX_FMT_YUV444P16BE,
00053         PIX_FMT_YUV444P,      PIX_FMT_YUV422P,
00054         PIX_FMT_YUV420P,      PIX_FMT_YUV411P,
00055         PIX_FMT_YUV410P,      PIX_FMT_YUV440P,
00056         PIX_FMT_YUVJ444P,     PIX_FMT_YUVJ422P,
00057         PIX_FMT_YUVJ420P,     PIX_FMT_YUVJ440P,
00058         PIX_FMT_YUVA420P,
00059         PIX_FMT_RGB8,         PIX_FMT_BGR8,
00060         PIX_FMT_RGB4_BYTE,    PIX_FMT_BGR4_BYTE,
00061         PIX_FMT_PAL8,         PIX_FMT_GRAY8,
00062         PIX_FMT_NONE
00063     };
00064 
00065     avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts));
00066     return 0;
00067 }
00068 
00069 static int config_props(AVFilterLink *inlink)
00070 {
00071     FlipContext *flip = inlink->dst->priv;
00072     const AVPixFmtDescriptor *pix_desc = &av_pix_fmt_descriptors[inlink->format];
00073 
00074     av_image_fill_max_pixsteps(flip->max_step, NULL, pix_desc);
00075     flip->hsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_w;
00076     flip->vsub = av_pix_fmt_descriptors[inlink->format].log2_chroma_h;
00077 
00078     return 0;
00079 }
00080 
00081 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
00082 {
00083     FlipContext *flip = inlink->dst->priv;
00084     AVFilterBufferRef *inpic  = inlink->cur_buf;
00085     AVFilterBufferRef *outpic = inlink->dst->outputs[0]->out_buf;
00086     uint8_t *inrow, *outrow;
00087     int i, j, plane, step, hsub, vsub;
00088 
00089     for (plane = 0; plane < 4 && inpic->data[plane]; plane++) {
00090         step = flip->max_step[plane];
00091         hsub = (plane == 1 || plane == 2) ? flip->hsub : 0;
00092         vsub = (plane == 1 || plane == 2) ? flip->vsub : 0;
00093 
00094         outrow = outpic->data[plane] + (y>>vsub) * outpic->linesize[plane];
00095         inrow  = inpic ->data[plane] + (y>>vsub) * inpic ->linesize[plane] + ((inlink->w >> hsub) - 1) * step;
00096         for (i = 0; i < h>>vsub; i++) {
00097             switch (step) {
00098             case 1:
00099             {
00100                 for (j = 0; j < (inlink->w >> hsub); j++)
00101                     outrow[j] = inrow[-j];
00102             }
00103             break;
00104 
00105             case 2:
00106             {
00107                 uint16_t *outrow16 = (uint16_t *)outrow;
00108                 uint16_t * inrow16 = (uint16_t *) inrow;
00109                 for (j = 0; j < (inlink->w >> hsub); j++)
00110                     outrow16[j] = inrow16[-j];
00111             }
00112             break;
00113 
00114             case 3:
00115             {
00116                 uint8_t *in  =  inrow;
00117                 uint8_t *out = outrow;
00118                 for (j = 0; j < (inlink->w >> hsub); j++, out += 3, in -= 3) {
00119                     int32_t v = AV_RB24(in);
00120                     AV_WB24(out, v);
00121                 }
00122             }
00123             break;
00124 
00125             case 4:
00126             {
00127                 uint32_t *outrow32 = (uint32_t *)outrow;
00128                 uint32_t * inrow32 = (uint32_t *) inrow;
00129                 for (j = 0; j < (inlink->w >> hsub); j++)
00130                     outrow32[j] = inrow32[-j];
00131             }
00132             break;
00133 
00134             default:
00135                 for (j = 0; j < (inlink->w >> hsub); j++)
00136                     memcpy(outrow + j*step, inrow - j*step, step);
00137             }
00138 
00139             inrow  += inpic ->linesize[plane];
00140             outrow += outpic->linesize[plane];
00141         }
00142     }
00143 
00144     avfilter_draw_slice(inlink->dst->outputs[0], y, h, slice_dir);
00145 }
00146 
00147 AVFilter avfilter_vf_hflip = {
00148     .name      = "hflip",
00149     .description = NULL_IF_CONFIG_SMALL("Horizontally flip the input video."),
00150     .priv_size = sizeof(FlipContext),
00151     .query_formats = query_formats,
00152 
00153     .inputs    = (AVFilterPad[]) {{ .name            = "default",
00154                                     .type            = AVMEDIA_TYPE_VIDEO,
00155                                     .draw_slice      = draw_slice,
00156                                     .config_props    = config_props,
00157                                     .min_perms       = AV_PERM_READ, },
00158                                   { .name = NULL}},
00159     .outputs   = (AVFilterPad[]) {{ .name            = "default",
00160                                     .type            = AVMEDIA_TYPE_VIDEO, },
00161                                   { .name = NULL}},
00162 };