1/*
2 * Copyright (c) 2012 Stefano Sabatini
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
23 * audio to video multimedia filter
24 */
25
26#include "libavutil/channel_layout.h"
27#include "libavutil/opt.h"
28#include "libavutil/parseutils.h"
29#include "avfilter.h"
30#include "formats.h"
31#include "audio.h"
32#include "video.h"
33#include "internal.h"
34
35enum ShowWavesMode {
36    MODE_POINT,
37    MODE_LINE,
38    MODE_NB,
39};
40
41typedef struct {
42    const AVClass *class;
43    int w, h;
44    AVRational rate;
45    int buf_idx;
46    AVFrame *outpicref;
47    int req_fullfilled;
48    int n;
49    int sample_count_mod;
50    enum ShowWavesMode mode;
51} ShowWavesContext;
52
53#define OFFSET(x) offsetof(ShowWavesContext, x)
54#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
55
56static const AVOption showwaves_options[] = {
57    { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0, FLAGS },
58    { "s",    "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "600x240"}, 0, 0, FLAGS },
59    { "mode", "select display mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_POINT}, 0, MODE_NB-1, FLAGS, "mode"},
60        { "point", "draw a point for each sample", 0, AV_OPT_TYPE_CONST, {.i64=MODE_POINT}, .flags=FLAGS, .unit="mode"},
61        { "line",  "draw a line for each sample",  0, AV_OPT_TYPE_CONST, {.i64=MODE_LINE},  .flags=FLAGS, .unit="mode"},
62    { "n",    "set how many samples to show in the same point", OFFSET(n), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, FLAGS },
63    { "rate", "set video rate", OFFSET(rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, FLAGS },
64    { "r",    "set video rate", OFFSET(rate), AV_OPT_TYPE_VIDEO_RATE, {.str = "25"}, 0, 0, FLAGS },
65    { NULL }
66};
67
68AVFILTER_DEFINE_CLASS(showwaves);
69
70static av_cold void uninit(AVFilterContext *ctx)
71{
72    ShowWavesContext *showwaves = ctx->priv;
73
74    av_frame_free(&showwaves->outpicref);
75}
76
77static int query_formats(AVFilterContext *ctx)
78{
79    AVFilterFormats *formats = NULL;
80    AVFilterChannelLayouts *layouts = NULL;
81    AVFilterLink *inlink = ctx->inputs[0];
82    AVFilterLink *outlink = ctx->outputs[0];
83    static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE };
84    static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
85
86    /* set input audio formats */
87    formats = ff_make_format_list(sample_fmts);
88    if (!formats)
89        return AVERROR(ENOMEM);
90    ff_formats_ref(formats, &inlink->out_formats);
91
92    layouts = ff_all_channel_layouts();
93    if (!layouts)
94        return AVERROR(ENOMEM);
95    ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts);
96
97    formats = ff_all_samplerates();
98    if (!formats)
99        return AVERROR(ENOMEM);
100    ff_formats_ref(formats, &inlink->out_samplerates);
101
102    /* set output video format */
103    formats = ff_make_format_list(pix_fmts);
104    if (!formats)
105        return AVERROR(ENOMEM);
106    ff_formats_ref(formats, &outlink->in_formats);
107
108    return 0;
109}
110
111static int config_output(AVFilterLink *outlink)
112{
113    AVFilterContext *ctx = outlink->src;
114    AVFilterLink *inlink = ctx->inputs[0];
115    ShowWavesContext *showwaves = ctx->priv;
116
117    if (!showwaves->n)
118        showwaves->n = FFMAX(1, ((double)inlink->sample_rate / (showwaves->w * av_q2d(showwaves->rate))) + 0.5);
119
120    showwaves->buf_idx = 0;
121    outlink->w = showwaves->w;
122    outlink->h = showwaves->h;
123    outlink->sample_aspect_ratio = (AVRational){1,1};
124
125    outlink->frame_rate = av_div_q((AVRational){inlink->sample_rate,showwaves->n},
126                                   (AVRational){showwaves->w,1});
127
128    av_log(ctx, AV_LOG_VERBOSE, "s:%dx%d r:%f n:%d\n",
129           showwaves->w, showwaves->h, av_q2d(outlink->frame_rate), showwaves->n);
130    return 0;
131}
132
133inline static int push_frame(AVFilterLink *outlink)
134{
135    ShowWavesContext *showwaves = outlink->src->priv;
136    int ret;
137
138    if ((ret = ff_filter_frame(outlink, showwaves->outpicref)) >= 0)
139        showwaves->req_fullfilled = 1;
140    showwaves->outpicref = NULL;
141    showwaves->buf_idx = 0;
142    return ret;
143}
144
145static int request_frame(AVFilterLink *outlink)
146{
147    ShowWavesContext *showwaves = outlink->src->priv;
148    AVFilterLink *inlink = outlink->src->inputs[0];
149    int ret;
150
151    showwaves->req_fullfilled = 0;
152    do {
153        ret = ff_request_frame(inlink);
154    } while (!showwaves->req_fullfilled && ret >= 0);
155
156    if (ret == AVERROR_EOF && showwaves->outpicref)
157        push_frame(outlink);
158    return ret;
159}
160
161#define MAX_INT16 ((1<<15) -1)
162
163static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
164{
165    AVFilterContext *ctx = inlink->dst;
166    AVFilterLink *outlink = ctx->outputs[0];
167    ShowWavesContext *showwaves = ctx->priv;
168    const int nb_samples = insamples->nb_samples;
169    AVFrame *outpicref = showwaves->outpicref;
170    int linesize = outpicref ? outpicref->linesize[0] : 0;
171    int16_t *p = (int16_t *)insamples->data[0];
172    int nb_channels = inlink->channels;
173    int i, j, k, h, ret = 0;
174    const int n = showwaves->n;
175    const int x = 255 / (nb_channels * n); /* multiplication factor, pre-computed to avoid in-loop divisions */
176
177    /* draw data in the buffer */
178    for (i = 0; i < nb_samples; i++) {
179        if (!showwaves->outpicref) {
180            showwaves->outpicref = outpicref =
181                ff_get_video_buffer(outlink, outlink->w, outlink->h);
182            if (!outpicref)
183                return AVERROR(ENOMEM);
184            outpicref->width  = outlink->w;
185            outpicref->height = outlink->h;
186            outpicref->pts = insamples->pts +
187                             av_rescale_q((p - (int16_t *)insamples->data[0]) / nb_channels,
188                                          (AVRational){ 1, inlink->sample_rate },
189                                          outlink->time_base);
190            linesize = outpicref->linesize[0];
191            for (j = 0; j < outlink->h; j++)
192                memset(outpicref->data[0] + j * linesize, 0, outlink->w);
193        }
194        for (j = 0; j < nb_channels; j++) {
195            h = showwaves->h/2 - av_rescale(*p++, showwaves->h/2, MAX_INT16);
196            switch (showwaves->mode) {
197            case MODE_POINT:
198                if (h >= 0 && h < outlink->h)
199                    *(outpicref->data[0] + showwaves->buf_idx + h * linesize) += x;
200                break;
201
202            case MODE_LINE:
203            {
204                int start = showwaves->h/2, end = av_clip(h, 0, outlink->h-1);
205                if (start > end) FFSWAP(int16_t, start, end);
206                for (k = start; k < end; k++)
207                    *(outpicref->data[0] + showwaves->buf_idx + k * linesize) += x;
208                break;
209            }
210            }
211        }
212
213        showwaves->sample_count_mod++;
214        if (showwaves->sample_count_mod == n) {
215            showwaves->sample_count_mod = 0;
216            showwaves->buf_idx++;
217        }
218        if (showwaves->buf_idx == showwaves->w)
219            if ((ret = push_frame(outlink)) < 0)
220                break;
221        outpicref = showwaves->outpicref;
222    }
223
224    av_frame_free(&insamples);
225    return ret;
226}
227
228static const AVFilterPad showwaves_inputs[] = {
229    {
230        .name         = "default",
231        .type         = AVMEDIA_TYPE_AUDIO,
232        .filter_frame = filter_frame,
233    },
234    { NULL }
235};
236
237static const AVFilterPad showwaves_outputs[] = {
238    {
239        .name          = "default",
240        .type          = AVMEDIA_TYPE_VIDEO,
241        .config_props  = config_output,
242        .request_frame = request_frame,
243    },
244    { NULL }
245};
246
247AVFilter ff_avf_showwaves = {
248    .name          = "showwaves",
249    .description   = NULL_IF_CONFIG_SMALL("Convert input audio to a video output."),
250    .uninit        = uninit,
251    .query_formats = query_formats,
252    .priv_size     = sizeof(ShowWavesContext),
253    .inputs        = showwaves_inputs,
254    .outputs       = showwaves_outputs,
255    .priv_class    = &showwaves_class,
256};
257