2 * Copyright (c) 2011 Mark Himsley
4 * This file is part of FFmpeg.
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * video field order filter, heavily influenced by vf_pad.c
31 #include "libavutil/imgutils.h"
32 #include "libavutil/internal.h"
33 #include "libavutil/pixdesc.h"
41 unsigned int dst_tff; ///< output bff/tff
42 int line_size[4]; ///< bytes of pixel data per line for each plane
45 static av_cold int init(AVFilterContext *ctx, const char *args)
47 FieldOrderContext *fieldorder = ctx->priv;
49 const char *tff = "tff";
50 const char *bff = "bff";
53 fieldorder->dst_tff = 1;
54 } else if (sscanf(args, "%u", &fieldorder->dst_tff) == 1) {
55 fieldorder->dst_tff = !!fieldorder->dst_tff;
56 } else if (!strcmp(tff, args)) {
57 fieldorder->dst_tff = 1;
58 } else if (!strcmp(bff, args)) {
59 fieldorder->dst_tff = 0;
61 av_log(ctx, AV_LOG_ERROR, "Invalid argument '%s'.\n", args);
62 return AVERROR(EINVAL);
65 av_log(ctx, AV_LOG_VERBOSE, "output field order: %s\n",
66 fieldorder->dst_tff ? tff : bff);
71 static int query_formats(AVFilterContext *ctx)
73 AVFilterFormats *formats;
74 enum PixelFormat pix_fmt;
77 /** accept any input pixel format that is not hardware accelerated, not
78 * a bitstream format, and does not have vertically sub-sampled chroma */
81 for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
82 if (!( av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_HWACCEL
83 || av_pix_fmt_descriptors[pix_fmt].flags & PIX_FMT_BITSTREAM)
84 && av_pix_fmt_descriptors[pix_fmt].nb_components
85 && !av_pix_fmt_descriptors[pix_fmt].log2_chroma_h
86 && (ret = ff_add_format(&formats, pix_fmt)) < 0) {
87 ff_formats_unref(&formats);
90 ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
91 ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
97 static int config_input(AVFilterLink *inlink)
99 AVFilterContext *ctx = inlink->dst;
100 FieldOrderContext *fieldorder = ctx->priv;
103 /** full an array with the number of bytes that the video
104 * data occupies per line for each plane of the input video */
105 for (plane = 0; plane < 4; plane++) {
106 fieldorder->line_size[plane] = av_image_get_linesize(
115 static AVFilterBufferRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h)
117 AVFilterContext *ctx = inlink->dst;
118 AVFilterLink *outlink = ctx->outputs[0];
120 return ff_get_video_buffer(outlink, perms, w, h);
123 static int start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref)
125 AVFilterContext *ctx = inlink->dst;
126 AVFilterLink *outlink = ctx->outputs[0];
128 AVFilterBufferRef *outpicref, *for_next_filter;
131 outpicref = avfilter_ref_buffer(inpicref, ~0);
133 return AVERROR(ENOMEM);
135 for_next_filter = avfilter_ref_buffer(outpicref, ~0);
136 if (!for_next_filter) {
137 avfilter_unref_bufferp(&outpicref);
138 return AVERROR(ENOMEM);
141 ret = ff_start_frame(outlink, for_next_filter);
143 avfilter_unref_bufferp(&outpicref);
147 outlink->out_buf = outpicref;
151 static int draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir)
153 AVFilterContext *ctx = inlink->dst;
154 FieldOrderContext *fieldorder = ctx->priv;
155 AVFilterLink *outlink = ctx->outputs[0];
157 AVFilterBufferRef *inpicref = inlink->cur_buf;
159 /** can only currently do slices if this filter is doing nothing
160 * because this filter is moving picture content, the output
161 * slice will contain different video lines than the input slice
162 * and that complexity will be added later */
163 if ( !inpicref->video->interlaced
164 || inpicref->video->top_field_first == fieldorder->dst_tff) {
165 return ff_draw_slice(outlink, y, h, slice_dir);
170 static int end_frame(AVFilterLink *inlink)
172 AVFilterContext *ctx = inlink->dst;
173 FieldOrderContext *fieldorder = ctx->priv;
174 AVFilterLink *outlink = ctx->outputs[0];
176 AVFilterBufferRef *inpicref = inlink->cur_buf;
177 AVFilterBufferRef *outpicref = outlink->out_buf;
179 int h, plane, line_step, line_size, line;
180 uint8_t *cpy_src, *cpy_dst;
182 if ( inpicref->video->interlaced
183 && inpicref->video->top_field_first != fieldorder->dst_tff) {
185 "picture will move %s one line\n",
186 fieldorder->dst_tff ? "up" : "down");
187 h = inpicref->video->h;
188 for (plane = 0; plane < 4 && inpicref->data[plane]; plane++) {
189 line_step = inpicref->linesize[plane];
190 line_size = fieldorder->line_size[plane];
191 cpy_src = inpicref->data[plane];
192 cpy_dst = outpicref->data[plane];
193 if (fieldorder->dst_tff) {
194 /** Move every line up one line, working from
195 * the top to the bottom of the frame.
196 * The original top line is lost.
197 * The new last line is created as a copy of the
198 * penultimate line from that field. */
199 for (line = 0; line < h; line++) {
200 if (1 + line < outpicref->video->h) {
201 memcpy(cpy_dst, cpy_src + line_step, line_size);
203 memcpy(cpy_dst, cpy_src - line_step - line_step, line_size);
205 cpy_src += line_step;
206 cpy_dst += line_step;
209 /** Move every line down one line, working from
210 * the bottom to the top of the frame.
211 * The original bottom line is lost.
212 * The new first line is created as a copy of the
213 * second line from that field. */
214 cpy_src += (h - 1) * line_step;
215 cpy_dst += (h - 1) * line_step;
216 for (line = h - 1; line >= 0 ; line--) {
218 memcpy(cpy_dst, cpy_src - line_step, line_size);
220 memcpy(cpy_dst, cpy_src + line_step + line_step, line_size);
222 cpy_src -= line_step;
223 cpy_dst -= line_step;
227 outpicref->video->top_field_first = fieldorder->dst_tff;
228 ff_draw_slice(outlink, 0, h, 1);
231 "not interlaced or field order already correct\n");
234 return ff_end_frame(outlink);
237 AVFilter avfilter_vf_fieldorder = {
238 .name = "fieldorder",
239 .description = NULL_IF_CONFIG_SMALL("Set the field order."),
241 .priv_size = sizeof(FieldOrderContext),
242 .query_formats = query_formats,
243 .inputs = (const AVFilterPad[]) {{ .name = "default",
244 .type = AVMEDIA_TYPE_VIDEO,
245 .config_props = config_input,
246 .start_frame = start_frame,
247 .get_video_buffer = get_video_buffer,
248 .draw_slice = draw_slice,
249 .end_frame = end_frame,
250 .min_perms = AV_PERM_READ | AV_PERM_PRESERVE },
252 .outputs = (const AVFilterPad[]) {{ .name = "default",
253 .type = AVMEDIA_TYPE_VIDEO, },