/* * Copyright (c) 2011 Mark Himsley * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * video field order filter, heavily influenced by vf_pad.c */ /* #define DEBUG */ #include "libavutil/imgutils.h" #include "libavutil/pixdesc.h" #include "avfilter.h" typedef struct { unsigned int dst_tff; ///< output bff/tff int line_size[4]; ///< bytes of pixel data per line for each plane } FieldOrderContext; static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) { FieldOrderContext *fieldorder = ctx->priv; const char *tff = "tff"; const char *bff = "bff"; if (!args) { fieldorder->dst_tff = 1; } else if (sscanf(args, "%u", &fieldorder->dst_tff) == 1) { fieldorder->dst_tff = !!fieldorder->dst_tff; } else if (!strcmp(tff, args)) { fieldorder->dst_tff = 1; } else if (!strcmp(bff, args)) { fieldorder->dst_tff = 0; } else { av_log(ctx, AV_LOG_ERROR, "Invalid argument '%s'.\n", args); return AVERROR(EINVAL); } av_log(ctx, AV_LOG_INFO, "output field order: %s\n", fieldorder->dst_tff ? tff : bff); return 0; } static int query_formats(AVFilterContext *ctx) { AVFilterFormats *formats; enum PixelFormat pix_fmt; int ret; /** accept any input pixel format that is not hardware accelerated, not * a bitstream format, and does not have vertically sub-sampled chroma */ if (ctx->inputs[0]) { formats = NULL; for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++) if (!( av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_HWACCEL || av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_BITSTREAM) && av_pix_fmt_descriptors[pix_fmt].nb_components && !av_pix_fmt_descriptors[pix_fmt].log2_chroma_h && (ret = avfilter_add_format(&formats, pix_fmt)) < 0) { avfilter_formats_unref(&formats); return ret; } avfilter_formats_ref(formats, &ctx->inputs[0]->out_formats); avfilter_formats_ref(formats, &ctx->outputs[0]->in_formats); } return 0; } static int config_input(AVFilterLink *inlink) { AVFilterContext *ctx = inlink->dst; FieldOrderContext *fieldorder = ctx->priv; int plane; /** full an array with the number of bytes that the video * data occupies per line for each plane of the input video */ for (plane = 0; plane < 4; plane++) { fieldorder->line_size[plane] = av_image_get_linesize( inlink->format, inlink->w, plane); } return 0; } static AVFilterBufferRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; return avfilter_get_video_buffer(outlink, perms, w, h); } static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; AVFilterBufferRef *outpicref; outpicref = avfilter_ref_buffer(inpicref, ~0); outlink->out_buf = outpicref; avfilter_start_frame(outlink, outpicref); } static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) { AVFilterContext *ctx = inlink->dst; FieldOrderContext *fieldorder = ctx->priv; AVFilterLink *outlink = ctx->outputs[0]; AVFilterBufferRef *inpicref = inlink->cur_buf; /** can only currently do slices if this filter is doing nothing * because this filter is moving picture content, the output * slice will contain different video lines than the input slice * and that complexity will be added later */ if ( !inpicref->video->interlaced || inpicref->video->top_field_first == fieldorder->dst_tff) { avfilter_draw_slice(outlink, y, h, slice_dir); } } static void end_frame(AVFilterLink *inlink) { AVFilterContext *ctx = inlink->dst; FieldOrderContext *fieldorder = ctx->priv; AVFilterLink *outlink = ctx->outputs[0]; AVFilterBufferRef *inpicref = inlink->cur_buf; AVFilterBufferRef *outpicref = outlink->out_buf; int h, plane, line_step, line_size, line; uint8_t *cpy_src, *cpy_dst; if ( inpicref->video->interlaced && inpicref->video->top_field_first != fieldorder->dst_tff) { av_dlog(ctx, "picture will move %s one line\n", fieldorder->dst_tff ? "up" : "down"); h = inpicref->video->h; for (plane = 0; plane < 4 && inpicref->data[plane]; plane++) { line_step = inpicref->linesize[plane]; line_size = fieldorder->line_size[plane]; cpy_src = inpicref->data[plane]; cpy_dst = outpicref->data[plane]; if (fieldorder->dst_tff) { /** Move every line up one line, working from * the top to the bottom of the frame. * The original top line is lost. * The new last line is created as a copy of the * penultimate line from that field. */ for (line = 0; line < h; line++) { if (1 + line < outpicref->video->h) { memcpy(cpy_dst, cpy_src + line_step, line_size); } else { memcpy(cpy_dst, cpy_src - line_step - line_step, line_size); } cpy_src += line_step; cpy_dst += line_step; } } else { /** Move every line down one line, working from * the bottom to the top of the frame. * The original bottom line is lost. * The new first line is created as a copy of the * second line from that field. */ cpy_src += (h - 1) * line_step; cpy_dst += (h - 1) * line_step; for (line = h - 1; line >= 0 ; line--) { if (line > 0) { memcpy(cpy_dst, cpy_src - line_step, line_size); } else { memcpy(cpy_dst, cpy_src + line_step + line_step, line_size); } cpy_src -= line_step; cpy_dst -= line_step; } } } outpicref->video->top_field_first = fieldorder->dst_tff; avfilter_draw_slice(outlink, 0, h, 1); } else { av_dlog(ctx, "not interlaced or field order already correct\n"); } avfilter_end_frame(outlink); avfilter_unref_buffer(inpicref); } AVFilter avfilter_vf_fieldorder = { .name = "fieldorder", .description = NULL_IF_CONFIG_SMALL("Set the field order."), .init = init, .priv_size = sizeof(FieldOrderContext), .query_formats = query_formats, .inputs = (const AVFilterPad[]) {{ .name = "default", .type = AVMEDIA_TYPE_VIDEO, .config_props = config_input, .start_frame = start_frame, .get_video_buffer = get_video_buffer, .draw_slice = draw_slice, .end_frame = end_frame, .min_perms = AV_PERM_READ, .rej_perms = AV_PERM_REUSE2|AV_PERM_PRESERVE,}, { .name = NULL}}, .outputs = (const AVFilterPad[]) {{ .name = "default", .type = AVMEDIA_TYPE_VIDEO, }, { .name = NULL}}, };