1/* 2 * Copyright (c) 2010 Brandon Mintern 3 * Copyright (c) 2007 Bobby Bingham 4 * 5 * This file is part of Libav. 6 * 7 * Libav is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * Libav is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with Libav; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * video fade filter 25 * based heavily on vf_negate.c by Bobby Bingham 26 */ 27 28#include "libavutil/pixdesc.h" 29#include "avfilter.h" 30 31typedef struct { 32 int factor, fade_per_frame; 33 unsigned int frame_index, start_frame, stop_frame; 34 int hsub, vsub, bpp; 35} FadeContext; 36 37static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) 38{ 39 FadeContext *fade = ctx->priv; 40 unsigned int nb_frames; 41 char in_out[4]; 42 43 if (!args || 44 sscanf(args, " %3[^:]:%u:%u", in_out, &fade->start_frame, &nb_frames) != 3) { 45 av_log(ctx, AV_LOG_ERROR, 46 "Expected 3 arguments '(in|out):#:#':'%s'\n", args); 47 return AVERROR(EINVAL); 48 } 49 50 nb_frames = nb_frames ? nb_frames : 1; 51 fade->fade_per_frame = (1 << 16) / nb_frames; 52 if (!strcmp(in_out, "in")) 53 fade->factor = 0; 54 else if (!strcmp(in_out, "out")) { 55 fade->fade_per_frame = -fade->fade_per_frame; 56 fade->factor = (1 << 16); 57 } else { 58 av_log(ctx, AV_LOG_ERROR, 59 "first argument must be 'in' or 'out':'%s'\n", in_out); 60 return AVERROR(EINVAL); 61 } 62 fade->stop_frame = fade->start_frame + nb_frames; 63 64 av_log(ctx, AV_LOG_INFO, 65 "type:%s start_frame:%d nb_frames:%d\n", 66 in_out, fade->start_frame, nb_frames); 67 return 0; 68} 69 70static int query_formats(AVFilterContext *ctx) 71{ 72 static const enum PixelFormat pix_fmts[] = { 73 PIX_FMT_YUV444P, PIX_FMT_YUV422P, PIX_FMT_YUV420P, 74 PIX_FMT_YUV411P, PIX_FMT_YUV410P, 75 PIX_FMT_YUVJ444P, PIX_FMT_YUVJ422P, PIX_FMT_YUVJ420P, 76 PIX_FMT_YUV440P, PIX_FMT_YUVJ440P, 77 PIX_FMT_RGB24, PIX_FMT_BGR24, 78 PIX_FMT_NONE 79 }; 80 81 avfilter_set_common_formats(ctx, avfilter_make_format_list(pix_fmts)); 82 return 0; 83} 84 85static int config_props(AVFilterLink *inlink) 86{ 87 FadeContext *fade = inlink->dst->priv; 88 const AVPixFmtDescriptor *pixdesc = &av_pix_fmt_descriptors[inlink->format]; 89 90 fade->hsub = pixdesc->log2_chroma_w; 91 fade->vsub = pixdesc->log2_chroma_h; 92 93 fade->bpp = av_get_bits_per_pixel(pixdesc) >> 3; 94 return 0; 95} 96 97static void draw_slice(AVFilterLink *inlink, int y, int h, int slice_dir) 98{ 99 FadeContext *fade = inlink->dst->priv; 100 AVFilterBufferRef *outpic = inlink->cur_buf; 101 uint8_t *p; 102 int i, j, plane; 103 104 if (fade->factor < UINT16_MAX) { 105 /* luma or rgb plane */ 106 for (i = 0; i < h; i++) { 107 p = outpic->data[0] + (y+i) * outpic->linesize[0]; 108 for (j = 0; j < inlink->w * fade->bpp; j++) { 109 /* fade->factor is using 16 lower-order bits for decimal 110 * places. 32768 = 1 << 15, it is an integer representation 111 * of 0.5 and is for rounding. */ 112 *p = (*p * fade->factor + 32768) >> 16; 113 p++; 114 } 115 } 116 117 if (outpic->data[1] && outpic->data[2]) { 118 /* chroma planes */ 119 for (plane = 1; plane < 3; plane++) { 120 for (i = 0; i < h; i++) { 121 p = outpic->data[plane] + ((y+i) >> fade->vsub) * outpic->linesize[plane]; 122 for (j = 0; j < inlink->w >> fade->hsub; j++) { 123 /* 8421367 = ((128 << 1) + 1) << 15. It is an integer 124 * representation of 128.5. The .5 is for rounding 125 * purposes. */ 126 *p = ((*p - 128) * fade->factor + 8421367) >> 16; 127 p++; 128 } 129 } 130 } 131 } 132 } 133 134 avfilter_draw_slice(inlink->dst->outputs[0], y, h, slice_dir); 135} 136 137static void end_frame(AVFilterLink *inlink) 138{ 139 FadeContext *fade = inlink->dst->priv; 140 141 avfilter_end_frame(inlink->dst->outputs[0]); 142 143 if (fade->frame_index >= fade->start_frame && 144 fade->frame_index <= fade->stop_frame) 145 fade->factor += fade->fade_per_frame; 146 fade->factor = av_clip_uint16(fade->factor); 147 fade->frame_index++; 148} 149 150AVFilter avfilter_vf_fade = { 151 .name = "fade", 152 .description = NULL_IF_CONFIG_SMALL("Fade in/out input video"), 153 .init = init, 154 .priv_size = sizeof(FadeContext), 155 .query_formats = query_formats, 156 157 .inputs = (AVFilterPad[]) {{ .name = "default", 158 .type = AVMEDIA_TYPE_VIDEO, 159 .config_props = config_props, 160 .get_video_buffer = avfilter_null_get_video_buffer, 161 .start_frame = avfilter_null_start_frame, 162 .draw_slice = draw_slice, 163 .end_frame = end_frame, 164 .min_perms = AV_PERM_READ | AV_PERM_WRITE, 165 .rej_perms = AV_PERM_PRESERVE, }, 166 { .name = NULL}}, 167 .outputs = (AVFilterPad[]) {{ .name = "default", 168 .type = AVMEDIA_TYPE_VIDEO, }, 169 { .name = NULL}}, 170}; 171