/* * Copyright (c) 2011 Stefano Sabatini * Copyright (c) 2010 Baptiste Coudurier * Copyright (c) 2003 Michael Zucchi * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 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 General Public License for more details. * * You should have received a copy of the GNU 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 * temporal field interlace filter, ported from MPlayer/libmpcodecs */ #include "libavutil/opt.h" #include "libavutil/imgutils.h" #include "libavutil/avassert.h" #include "avfilter.h" #include "internal.h" enum TInterlaceMode { MODE_MERGE = 0, MODE_DROP_EVEN, MODE_DROP_ODD, MODE_PAD, MODE_INTERLEAVE_TOP, MODE_INTERLEAVE_BOTTOM, MODE_INTERLACEX2, MODE_NB, }; typedef struct { const AVClass *class; enum TInterlaceMode mode; ///< interlace mode selected int flags; ///< flags affecting interlacing algorithm int frame; ///< number of the output frame int vsub; ///< chroma vertical subsampling AVFilterBufferRef *cur; AVFilterBufferRef *next; uint8_t *black_data[4]; ///< buffer used to fill padded lines int black_linesize[4]; } TInterlaceContext; #define OFFSET(x) offsetof(TInterlaceContext, x) #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM #define TINTERLACE_FLAG_VLPF 01 static const AVOption tinterlace_options[] = { {"mode", "select interlace mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_MERGE}, 0, MODE_NB-1, FLAGS, "mode"}, {"merge", "merge fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_MERGE}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"drop_even", "drop even fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_DROP_EVEN}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"drop_odd", "drop odd fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_DROP_ODD}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"pad", "pad alternate lines with black", 0, AV_OPT_TYPE_CONST, {.i64=MODE_PAD}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"interleave_top", "interleave top and bottom fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLEAVE_TOP}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"interleave_bottom", "interleave bottom and top fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLEAVE_BOTTOM}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"interlacex2", "interlace fields from two consecutive frames", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLACEX2}, INT_MIN, INT_MAX, FLAGS, "mode"}, {"flags", "set flags", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, INT_MAX, 0, "flags" }, {"low_pass_filter", "enable vertical low-pass filter", 0, AV_OPT_TYPE_CONST, {.i64 = TINTERLACE_FLAG_VLPF}, INT_MIN, INT_MAX, FLAGS, "flags" }, {"vlpf", "enable vertical low-pass filter", 0, AV_OPT_TYPE_CONST, {.i64 = TINTERLACE_FLAG_VLPF}, INT_MIN, INT_MAX, FLAGS, "flags" }, {NULL} }; AVFILTER_DEFINE_CLASS(tinterlace); #define FULL_SCALE_YUVJ_FORMATS \ AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P static enum AVPixelFormat full_scale_yuvj_pix_fmts[] = { FULL_SCALE_YUVJ_FORMATS, AV_PIX_FMT_NONE }; static int query_formats(AVFilterContext *ctx) { static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUVA420P, AV_PIX_FMT_GRAY8, FULL_SCALE_YUVJ_FORMATS, AV_PIX_FMT_NONE }; ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); return 0; } static av_cold int init(AVFilterContext *ctx, const char *args) { TInterlaceContext *tinterlace = ctx->priv; static const char *shorthand[] = { "mode", NULL }; tinterlace->class = &tinterlace_class; av_opt_set_defaults(tinterlace); return av_opt_set_from_string(tinterlace, args, shorthand, "=", ":"); } static av_cold void uninit(AVFilterContext *ctx) { TInterlaceContext *tinterlace = ctx->priv; avfilter_unref_bufferp(&tinterlace->cur ); avfilter_unref_bufferp(&tinterlace->next); av_opt_free(tinterlace); av_freep(&tinterlace->black_data[0]); } static int config_out_props(AVFilterLink *outlink) { AVFilterContext *ctx = outlink->src; AVFilterLink *inlink = outlink->src->inputs[0]; const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format); TInterlaceContext *tinterlace = ctx->priv; tinterlace->vsub = desc->log2_chroma_h; outlink->w = inlink->w; outlink->h = tinterlace->mode == MODE_MERGE || tinterlace->mode == MODE_PAD ? inlink->h*2 : inlink->h; if (tinterlace->mode == MODE_PAD) { uint8_t black[4] = { 16, 128, 128, 16 }; int i, ret; if (ff_fmt_is_in(outlink->format, full_scale_yuvj_pix_fmts)) black[0] = black[3] = 0; ret = av_image_alloc(tinterlace->black_data, tinterlace->black_linesize, outlink->w, outlink->h, outlink->format, 1); if (ret < 0) return ret; /* fill black picture with black */ for (i = 0; i < 4 && tinterlace->black_data[i]; i++) { int h = i == 1 || i == 2 ? outlink->h >> desc->log2_chroma_h : outlink->h; memset(tinterlace->black_data[i], black[i], tinterlace->black_linesize[i] * h); } } if ((tinterlace->flags & TINTERLACE_FLAG_VLPF) && !(tinterlace->mode == MODE_INTERLEAVE_TOP || tinterlace->mode == MODE_INTERLEAVE_BOTTOM)) { av_log(ctx, AV_LOG_WARNING, "low_pass_filter flag ignored with mode %d\n", tinterlace->mode); tinterlace->flags &= ~TINTERLACE_FLAG_VLPF; } av_log(ctx, AV_LOG_VERBOSE, "mode:%d filter:%s h:%d -> h:%d\n", tinterlace->mode, (tinterlace->flags & TINTERLACE_FLAG_VLPF) ? "on" : "off", inlink->h, outlink->h); return 0; } #define FIELD_UPPER 0 #define FIELD_LOWER 1 #define FIELD_UPPER_AND_LOWER 2 /** * Copy picture field from src to dst. * * @param src_field copy from upper, lower field or both * @param interleave leave a padding line between each copied line * @param dst_field copy to upper or lower field, * only meaningful when interleave is selected * @param flags context flags */ static inline void copy_picture_field(uint8_t *dst[4], int dst_linesize[4], const uint8_t *src[4], int src_linesize[4], enum AVPixelFormat format, int w, int src_h, int src_field, int interleave, int dst_field, int flags) { const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(format); int plane, vsub = desc->log2_chroma_h; int k = src_field == FIELD_UPPER_AND_LOWER ? 1 : 2; int h, i; for (plane = 0; plane < desc->nb_components; plane++) { int lines = plane == 1 || plane == 2 ? src_h >> vsub : src_h; int linesize = av_image_get_linesize(format, w, plane); uint8_t *dstp = dst[plane]; const uint8_t *srcp = src[plane]; if (linesize < 0) return; lines /= k; if (src_field == FIELD_LOWER) srcp += src_linesize[plane]; if (interleave && dst_field == FIELD_LOWER) dstp += dst_linesize[plane]; if (flags & TINTERLACE_FLAG_VLPF) { // Low-pass filtering is required when creating an interlaced destination from // a progressive source which contains high-frequency vertical detail. // Filtering will reduce interlace 'twitter' and Moire patterning. int srcp_linesize = src_linesize[plane] * k; int dstp_linesize = dst_linesize[plane] * (interleave ? 2 : 1); for (h = lines; h > 0; h--) { const uint8_t *srcp_above = srcp - src_linesize[plane]; const uint8_t *srcp_below = srcp + src_linesize[plane]; if (h == lines) srcp_above = srcp; // there is no line above if (h == 1) srcp_below = srcp; // there is no line below for (i = 0; i < linesize; i++) { // this calculation is an integer representation of // '0.5 * current + 0.25 * above + 0.25 + below' // '1 +' is for rounding. */ dstp[i] = (1 + srcp[i] + srcp[i] + srcp_above[i] + srcp_below[i]) >> 2; } dstp += dstp_linesize; srcp += srcp_linesize; } } else { av_image_copy_plane(dstp, dst_linesize[plane] * (interleave ? 2 : 1), srcp, src_linesize[plane]*k, linesize, lines); } } } static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *picref) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; TInterlaceContext *tinterlace = ctx->priv; AVFilterBufferRef *cur, *next, *out; int field, tff, ret; avfilter_unref_buffer(tinterlace->cur); tinterlace->cur = tinterlace->next; tinterlace->next = picref; cur = tinterlace->cur; next = tinterlace->next; /* we need at least two frames */ if (!tinterlace->cur) return 0; switch (tinterlace->mode) { case MODE_MERGE: /* move the odd frame into the upper field of the new image, even into * the lower field, generating a double-height video at half framerate */ out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h); if (!out) return AVERROR(ENOMEM); avfilter_copy_buffer_ref_props(out, cur); out->video->h = outlink->h; out->video->interlaced = 1; out->video->top_field_first = 1; /* write odd frame lines into the upper field of the new frame */ copy_picture_field(out->data, out->linesize, (const uint8_t **)cur->data, cur->linesize, inlink->format, inlink->w, inlink->h, FIELD_UPPER_AND_LOWER, 1, FIELD_UPPER, tinterlace->flags); /* write even frame lines into the lower field of the new frame */ copy_picture_field(out->data, out->linesize, (const uint8_t **)next->data, next->linesize, inlink->format, inlink->w, inlink->h, FIELD_UPPER_AND_LOWER, 1, FIELD_LOWER, tinterlace->flags); avfilter_unref_bufferp(&tinterlace->next); break; case MODE_DROP_ODD: /* only output even frames, odd frames are dropped; height unchanged, half framerate */ case MODE_DROP_EVEN: /* only output odd frames, even frames are dropped; height unchanged, half framerate */ out = avfilter_ref_buffer(tinterlace->mode == MODE_DROP_EVEN ? cur : next, AV_PERM_READ); avfilter_unref_bufferp(&tinterlace->next); break; case MODE_PAD: /* expand each frame to double height, but pad alternate * lines with black; framerate unchanged */ out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h); avfilter_copy_buffer_ref_props(out, cur); out->video->h = outlink->h; field = (1 + tinterlace->frame) & 1 ? FIELD_UPPER : FIELD_LOWER; /* copy upper and lower fields */ copy_picture_field(out->data, out->linesize, (const uint8_t **)cur->data, cur->linesize, inlink->format, inlink->w, inlink->h, FIELD_UPPER_AND_LOWER, 1, field, tinterlace->flags); /* pad with black the other field */ copy_picture_field(out->data, out->linesize, (const uint8_t **)tinterlace->black_data, tinterlace->black_linesize, inlink->format, inlink->w, inlink->h, FIELD_UPPER_AND_LOWER, 1, !field, tinterlace->flags); break; /* interleave upper/lower lines from odd frames with lower/upper lines from even frames, * halving the frame rate and preserving image height */ case MODE_INTERLEAVE_TOP: /* top field first */ case MODE_INTERLEAVE_BOTTOM: /* bottom field first */ tff = tinterlace->mode == MODE_INTERLEAVE_TOP; out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h); if (!out) return AVERROR(ENOMEM); avfilter_copy_buffer_ref_props(out, cur); out->video->interlaced = 1; out->video->top_field_first = tff; /* copy upper/lower field from cur */ copy_picture_field(out->data, out->linesize, (const uint8_t **)cur->data, cur->linesize, inlink->format, inlink->w, inlink->h, tff ? FIELD_UPPER : FIELD_LOWER, 1, tff ? FIELD_UPPER : FIELD_LOWER, tinterlace->flags); /* copy lower/upper field from next */ copy_picture_field(out->data, out->linesize, (const uint8_t **)next->data, next->linesize, inlink->format, inlink->w, inlink->h, tff ? FIELD_LOWER : FIELD_UPPER, 1, tff ? FIELD_LOWER : FIELD_UPPER, tinterlace->flags); avfilter_unref_bufferp(&tinterlace->next); break; case MODE_INTERLACEX2: /* re-interlace preserving image height, double frame rate */ /* output current frame first */ out = avfilter_ref_buffer(cur, ~AV_PERM_WRITE); if (!out) return AVERROR(ENOMEM); out->video->interlaced = 1; if ((ret = ff_filter_frame(outlink, out)) < 0) return ret; /* output mix of current and next frame */ tff = next->video->top_field_first; out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h); if (!out) return AVERROR(ENOMEM); avfilter_copy_buffer_ref_props(out, next); out->video->interlaced = 1; /* write current frame second field lines into the second field of the new frame */ copy_picture_field(out->data, out->linesize, (const uint8_t **)cur->data, cur->linesize, inlink->format, inlink->w, inlink->h, tff ? FIELD_LOWER : FIELD_UPPER, 1, tff ? FIELD_LOWER : FIELD_UPPER, tinterlace->flags); /* write next frame first field lines into the first field of the new frame */ copy_picture_field(out->data, out->linesize, (const uint8_t **)next->data, next->linesize, inlink->format, inlink->w, inlink->h, tff ? FIELD_UPPER : FIELD_LOWER, 1, tff ? FIELD_UPPER : FIELD_LOWER, tinterlace->flags); break; default: av_assert0(0); } ret = ff_filter_frame(outlink, out); tinterlace->frame++; return ret; } static int request_frame(AVFilterLink *outlink) { TInterlaceContext *tinterlace = outlink->src->priv; AVFilterLink *inlink = outlink->src->inputs[0]; do { int ret; if ((ret = ff_request_frame(inlink)) < 0) return ret; } while (!tinterlace->cur); return 0; } static const AVFilterPad tinterlace_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .filter_frame = filter_frame, }, { NULL } }; static const AVFilterPad tinterlace_outputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .config_props = config_out_props, .request_frame = request_frame, }, { NULL } }; AVFilter avfilter_vf_tinterlace = { .name = "tinterlace", .description = NULL_IF_CONFIG_SMALL("Perform temporal field interlacing."), .priv_size = sizeof(TInterlaceContext), .init = init, .uninit = uninit, .query_formats = query_formats, .inputs = tinterlace_inputs, .outputs = tinterlace_outputs, .priv_class = &tinterlace_class, };