Make the scale filter pass the pkt.pos information to the output
[libav.git] / libavfilter / vf_scale.c
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1/*
2 * copyright (c) 2007 Bobby Bingham
3 *
4 * This file is part of FFmpeg.
5 *
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.
10 *
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.
15 *
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
19 */
20
21/**
22 * @file libavfilter/vf_scale.c
23 * scale video filter
24 */
25
26#include "avfilter.h"
b4b66456 27#include "libavutil/pixdesc.h"
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28#include "libswscale/swscale.h"
29
30typedef struct {
31 struct SwsContext *sws; ///< software scaler context
32
33 /**
34 * New dimensions. Special values are:
35 * 0 = original width/height
36 * -1 = keep original aspect
37 */
38 int w, h;
39
40 int hsub, vsub; ///< chroma subsampling
41 int slice_y; ///< top of current output slice
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42 int input_is_pal; ///< set to 1 if the input format is paletted
43} ScaleContext;
44
45static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque)
46{
47 ScaleContext *scale = ctx->priv;
48
49 if (args)
50 sscanf(args, "%d:%d", &scale->w, &scale->h);
51
52 /* sanity check params */
53 if (scale->w < -1 || scale->h < -1) {
54 av_log(ctx, AV_LOG_ERROR, "Size values less than -1 are not acceptable.\n");
55 return -1;
56 }
57 if (scale->w == -1 && scale->h == -1)
58 scale->w = scale->h = 0;
59
60 return 0;
61}
62
63static av_cold void uninit(AVFilterContext *ctx)
64{
65 ScaleContext *scale = ctx->priv;
66 sws_freeContext(scale->sws);
67 scale->sws = NULL;
68}
69
70static int query_formats(AVFilterContext *ctx)
71{
72 AVFilterFormats *formats;
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73 enum PixelFormat pix_fmt;
74 int ret;
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75
76 if (ctx->inputs[0]) {
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77 formats = NULL;
78 for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
79 if ( sws_isSupportedInput(pix_fmt)
80 && (ret = avfilter_add_colorspace(&formats, pix_fmt)) < 0) {
81 avfilter_formats_unref(&formats);
82 return ret;
83 }
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84 avfilter_formats_ref(formats, &ctx->inputs[0]->out_formats);
85 }
86 if (ctx->outputs[0]) {
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87 formats = NULL;
88 for (pix_fmt = 0; pix_fmt < PIX_FMT_NB; pix_fmt++)
89 if ( sws_isSupportedOutput(pix_fmt)
90 && (ret = avfilter_add_colorspace(&formats, pix_fmt)) < 0) {
91 avfilter_formats_unref(&formats);
92 return ret;
93 }
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94 avfilter_formats_ref(formats, &ctx->outputs[0]->in_formats);
95 }
96
97 return 0;
98}
99
100static int config_props(AVFilterLink *outlink)
101{
102 AVFilterContext *ctx = outlink->src;
103 AVFilterLink *inlink = outlink->src->inputs[0];
104 ScaleContext *scale = ctx->priv;
105 int64_t w, h;
106
107 if (!(w = scale->w))
108 w = inlink->w;
109 if (!(h = scale->h))
110 h = inlink->h;
111 if (w == -1)
112 w = av_rescale(h, inlink->w, inlink->h);
113 if (h == -1)
114 h = av_rescale(w, inlink->h, inlink->w);
115
116 if (w > INT_MAX || h > INT_MAX ||
117 (h * inlink->w) > INT_MAX ||
118 (w * inlink->h) > INT_MAX)
119 av_log(ctx, AV_LOG_ERROR, "Rescaled value for width or height is too big.\n");
120
121 outlink->w = w;
122 outlink->h = h;
123
124 /* TODO: make algorithm configurable */
125 scale->sws = sws_getContext(inlink ->w, inlink ->h, inlink ->format,
126 outlink->w, outlink->h, outlink->format,
127 SWS_BILINEAR, NULL, NULL, NULL);
128
129 av_log(ctx, AV_LOG_INFO, "w:%d h:%d fmt:%s\n",
b4b66456 130 outlink->w, outlink->h, av_pix_fmt_descriptors[outlink->format].name);
c3eabb7d 131
d2a2b08c 132 scale->input_is_pal = av_pix_fmt_descriptors[inlink->format].flags & PIX_FMT_PAL;
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133
134 return !scale->sws;
135}
136
137static void start_frame(AVFilterLink *link, AVFilterPicRef *picref)
138{
139 ScaleContext *scale = link->dst->priv;
140 AVFilterLink *outlink = link->dst->outputs[0];
141 AVFilterPicRef *outpicref;
142
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143 scale->hsub = av_pix_fmt_descriptors[link->format].log2_chroma_w;
144 scale->vsub = av_pix_fmt_descriptors[link->format].log2_chroma_h;
b37aa4de 145
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146 outpicref = avfilter_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
147 outpicref->pts = picref->pts;
89fb9ae9 148 outpicref->pos = picref->pos;
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149 outlink->outpic = outpicref;
150
151 av_reduce(&outpicref->pixel_aspect.num, &outpicref->pixel_aspect.den,
152 (int64_t)picref->pixel_aspect.num * outlink->h * link->w,
153 (int64_t)picref->pixel_aspect.den * outlink->w * link->h,
154 INT_MAX);
155
a13a5437 156 scale->slice_y = 0;
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157 avfilter_start_frame(outlink, avfilter_ref_pic(outpicref, ~0));
158}
159
a13a5437 160static void draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
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161{
162 ScaleContext *scale = link->dst->priv;
163 int out_h;
164 AVFilterPicRef *cur_pic = link->cur_pic;
165 uint8_t *data[4];
166
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167 if (scale->slice_y == 0 && slice_dir == -1)
168 scale->slice_y = link->dst->outputs[0]->h;
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169
170 data[0] = cur_pic->data[0] + y * cur_pic->linesize[0];
171 data[1] = scale->input_is_pal ?
172 cur_pic->data[1] :
173 cur_pic->data[1] + (y>>scale->vsub) * cur_pic->linesize[1];
174 data[2] = cur_pic->data[2] + (y>>scale->vsub) * cur_pic->linesize[2];
175 data[3] = cur_pic->data[3] + y * cur_pic->linesize[3];
176
177 out_h = sws_scale(scale->sws, data, cur_pic->linesize, y, h,
178 link->dst->outputs[0]->outpic->data,
179 link->dst->outputs[0]->outpic->linesize);
180
a13a5437 181 if (slice_dir == -1)
c3eabb7d 182 scale->slice_y -= out_h;
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183 avfilter_draw_slice(link->dst->outputs[0], scale->slice_y, out_h, slice_dir);
184 if (slice_dir == 1)
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185 scale->slice_y += out_h;
186}
187
188AVFilter avfilter_vf_scale = {
189 .name = "scale",
190 .description = "Scale the input video to width:height size and/or convert the image format.",
191
192 .init = init,
193 .uninit = uninit,
194
195 .query_formats = query_formats,
196
197 .priv_size = sizeof(ScaleContext),
198
199 .inputs = (AVFilterPad[]) {{ .name = "default",
200 .type = CODEC_TYPE_VIDEO,
201 .start_frame = start_frame,
202 .draw_slice = draw_slice,
203 .min_perms = AV_PERM_READ, },
204 { .name = NULL}},
205 .outputs = (AVFilterPad[]) {{ .name = "default",
206 .type = CODEC_TYPE_VIDEO,
207 .config_props = config_props, },
208 { .name = NULL}},
209};