libavfilter/vf_fieldorder.c
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00001 /*
00002  * Copyright (c) 2011 Mark Himsley
00003  *
00004  * This file is part of Libav.
00005  *
00006  * Libav is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * Libav is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with Libav; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00026 /* #define DEBUG */
00027 
00028 #include "libavutil/imgutils.h"
00029 #include "libavutil/pixdesc.h"
00030 #include "avfilter.h"
00031 
00032 typedef struct
00033 {
00034     unsigned int dst_tff;      
00035     int          line_size[4]; 
00036 } FieldOrderContext;
00037 
00038 static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
00039 {
00040     FieldOrderContext *fieldorder = ctx->priv;
00041 
00042     const char *tff = "tff";
00043     const char *bff = "bff";
00044 
00045     if (!args) {
00046         fieldorder->dst_tff = 1;
00047     } else if (sscanf(args, "%u", &fieldorder->dst_tff) == 1) {
00048         fieldorder->dst_tff = !!fieldorder->dst_tff;
00049     } else if (!strcmp(tff, args)) {
00050         fieldorder->dst_tff = 1;
00051     } else if (!strcmp(bff, args)) {
00052         fieldorder->dst_tff = 0;
00053     } else {
00054         av_log(ctx, AV_LOG_ERROR, "Invalid argument '%s'.\n", args);
00055         return AVERROR(EINVAL);
00056     }
00057 
00058     av_log(ctx, AV_LOG_INFO, "output field order: %s\n",
00059             fieldorder->dst_tff ? tff : bff);
00060 
00061     return 0;
00062 }
00063 
00064 static int query_formats(AVFilterContext *ctx)
00065 {
00066     AVFilterFormats  *formats;
00067     enum PixelFormat pix_fmt;
00068     int              ret;
00069 
00072     if (ctx->inputs[0]) {
00073         formats = NULL;
00074         for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
00075             if (!(  av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_HWACCEL
00076                  || av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_BITSTREAM)
00077                 && av_pix_fmt_descriptors[pix_fmt].nb_components
00078                 && !av_pix_fmt_descriptors[pix_fmt].log2_chroma_h
00079                 && (ret = avfilter_add_format(&formats, pix_fmt)) < 0) {
00080                 avfilter_formats_unref(&formats);
00081                 return ret;
00082             }
00083         avfilter_formats_ref(formats, &ctx->inputs[0]->out_formats);
00084         avfilter_formats_ref(formats, &ctx->outputs[0]->in_formats);
00085     }
00086 
00087     return 0;
00088 }
00089 
00090 static int config_input(AVFilterLink *inlink)
00091 {
00092     AVFilterContext   *ctx        = inlink->dst;
00093     FieldOrderContext *fieldorder = ctx->priv;
00094     int               plane;
00095 
00098     for (plane = 0; plane < 4; plane++) {
00099         fieldorder->line_size[plane] = av_image_get_linesize(
00100                 inlink->format,
00101                 inlink->w,
00102                 plane);
00103     }
00104 
00105     return 0;
00106 }
00107 
00108 static AVFilterBufferRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h)
00109 {
00110     AVFilterContext   *ctx        = inlink->dst;
00111     AVFilterLink      *outlink    = ctx->outputs[0];
00112 
00113     return avfilter_get_video_buffer(outlink, perms, w, h);
00114 }
00115 
00116 static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
00117 {
00118     AVFilterContext   *ctx        = inlink->dst;
00119     AVFilterLink      *outlink    = ctx->outputs[0];
00120 
00121     AVFilterBufferRef *outpicref;
00122 
00123     outpicref = avfilter_ref_buffer(inpicref, ~0);
00124     outlink->out_buf = outpicref;
00125 
00126     avfilter_start_frame(outlink, outpicref);
00127 }
00128 
00129 static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
00130 {
00131     AVFilterContext   *ctx        = inlink->dst;
00132     FieldOrderContext *fieldorder = ctx->priv;
00133     AVFilterLink      *outlink    = ctx->outputs[0];
00134 
00135     AVFilterBufferRef *inpicref   = inlink->cur_buf;
00136 
00141     if (  !inpicref->video->interlaced
00142         || inpicref->video->top_field_first == fieldorder->dst_tff) {
00143         avfilter_draw_slice(outlink, y, h, slice_dir);
00144     }
00145 }
00146 
00147 static void end_frame(AVFilterLink *inlink)
00148 {
00149     AVFilterContext   *ctx        = inlink->dst;
00150     FieldOrderContext *fieldorder = ctx->priv;
00151     AVFilterLink      *outlink    = ctx->outputs[0];
00152 
00153     AVFilterBufferRef *inpicref   = inlink->cur_buf;
00154     AVFilterBufferRef *outpicref  = outlink->out_buf;
00155 
00156     int               h, plane, line_step, line_size, line;
00157     uint8_t           *cpy_src, *cpy_dst;
00158 
00159     if (    inpicref->video->interlaced
00160          && inpicref->video->top_field_first != fieldorder->dst_tff) {
00161         av_dlog(ctx,
00162                 "picture will move %s one line\n",
00163                 fieldorder->dst_tff ? "up" : "down");
00164         h = inpicref->video->h;
00165         for (plane = 0; plane < 4 && inpicref->data[plane]; plane++) {
00166             line_step = inpicref->linesize[plane];
00167             line_size = fieldorder->line_size[plane];
00168             cpy_src = inpicref->data[plane];
00169             cpy_dst = outpicref->data[plane];
00170             if (fieldorder->dst_tff) {
00176                 for (line = 0; line < h; line++) {
00177                     if (1 + line < outpicref->video->h) {
00178                         memcpy(cpy_dst, cpy_src + line_step, line_size);
00179                     } else {
00180                         memcpy(cpy_dst, cpy_src - line_step - line_step, line_size);
00181                     }
00182                     cpy_src += line_step;
00183                     cpy_dst += line_step;
00184                 }
00185             } else {
00191                 cpy_src += (h - 1) * line_step;
00192                 cpy_dst += (h - 1) * line_step;
00193                 for (line = h - 1; line >= 0 ; line--) {
00194                     if (line > 0) {
00195                         memcpy(cpy_dst, cpy_src - line_step, line_size);
00196                     } else {
00197                         memcpy(cpy_dst, cpy_src + line_step + line_step, line_size);
00198                     }
00199                     cpy_src -= line_step;
00200                     cpy_dst -= line_step;
00201                 }
00202             }
00203         }
00204         outpicref->video->top_field_first = fieldorder->dst_tff;
00205         avfilter_draw_slice(outlink, 0, h, 1);
00206     } else {
00207         av_dlog(ctx,
00208                 "not interlaced or field order already correct\n");
00209     }
00210 
00211     avfilter_end_frame(outlink);
00212     avfilter_unref_buffer(inpicref);
00213 }
00214 
00215 AVFilter avfilter_vf_fieldorder = {
00216     .name          = "fieldorder",
00217     .description   = NULL_IF_CONFIG_SMALL("Set the field order."),
00218     .init          = init,
00219     .priv_size     = sizeof(FieldOrderContext),
00220     .query_formats = query_formats,
00221     .inputs        = (AVFilterPad[]) {{ .name             = "default",
00222                                         .type             = AVMEDIA_TYPE_VIDEO,
00223                                         .config_props     = config_input,
00224                                         .start_frame      = start_frame,
00225                                         .get_video_buffer = get_video_buffer,
00226                                         .draw_slice       = draw_slice,
00227                                         .end_frame        = end_frame,
00228                                         .min_perms        = AV_PERM_READ,
00229                                         .rej_perms        = AV_PERM_REUSE2|AV_PERM_PRESERVE,},
00230                                       { .name = NULL}},
00231     .outputs       = (AVFilterPad[]) {{ .name             = "default",
00232                                         .type             = AVMEDIA_TYPE_VIDEO, },
00233                                       { .name = NULL}},
00234 };