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avf_showcqt.c
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1 /*
2  * Copyright (c) 2014 Muhammad Faiz <mfcc64@gmail.com>
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 #include "config.h"
22 #include "libavcodec/avfft.h"
23 #include "libavutil/avassert.h"
24 #include "libavutil/channel_layout.h"
25 #include "libavutil/opt.h"
26 #include "libavutil/xga_font_data.h"
27 #include "libavutil/qsort.h"
28 #include "libavutil/time.h"
29 #include "libavutil/eval.h"
30 #include "avfilter.h"
31 #include "internal.h"
32 
33 #include <math.h>
34 #include <stdlib.h>
35 
36 #if CONFIG_LIBFREETYPE
37 #include <ft2build.h>
38 #include FT_FREETYPE_H
39 #endif
40 
41 /* this filter is designed to do 16 bins/semitones constant Q transform with Brown-Puckette algorithm
42  * start from E0 to D#10 (10 octaves)
43  * so there are 16 bins/semitones * 12 semitones/octaves * 10 octaves = 1920 bins
44  * match with full HD resolution */
45 
46 #define VIDEO_WIDTH 1920
47 #define VIDEO_HEIGHT 1080
48 #define FONT_HEIGHT 32
49 #define SPECTOGRAM_HEIGHT ((VIDEO_HEIGHT-FONT_HEIGHT)/2)
50 #define SPECTOGRAM_START (VIDEO_HEIGHT-SPECTOGRAM_HEIGHT)
51 #define BASE_FREQ 20.051392800492
52 #define COEFF_CLAMP 1.0e-4
53 #define TLENGTH_MIN 0.001
54 #define TLENGTH_DEFAULT "384/f*tc/(384/f+tc)"
55 #define VOLUME_MIN 1e-10
56 #define VOLUME_MAX 100.0
57 #define FONTCOLOR_DEFAULT "st(0, (midi(f)-59.5)/12);" \
58  "st(1, if(between(ld(0),0,1), 0.5-0.5*cos(2*PI*ld(0)), 0));" \
59  "r(1-ld(1)) + b(ld(1))"
60 
61 typedef struct {
62  FFTSample value;
63  int index;
64 } SparseCoeff;
65 
66 typedef struct {
67  const AVClass *class;
68  AVFrame *outpicref;
69  FFTContext *fft_context;
70  FFTComplex *fft_data;
71  FFTComplex *fft_result_left;
72  FFTComplex *fft_result_right;
73  uint8_t *spectogram;
74  SparseCoeff *coeff_sort;
75  SparseCoeff *coeffs[VIDEO_WIDTH];
76  uint8_t *font_alpha;
77  char *fontfile; /* using freetype */
78  int coeffs_len[VIDEO_WIDTH];
79  uint8_t fontcolor_value[VIDEO_WIDTH*3]; /* result of fontcolor option */
80  int64_t frame_count;
81  int spectogram_count;
82  int spectogram_index;
83  int fft_bits;
84  int req_fullfilled;
85  int remaining_fill;
86  char *tlength;
87  char *volume;
88  char *fontcolor;
89  double timeclamp; /* lower timeclamp, time-accurate, higher timeclamp, freq-accurate (at low freq)*/
90  float coeffclamp; /* lower coeffclamp, more precise, higher coeffclamp, faster */
91  int fullhd; /* if true, output video is at full HD resolution, otherwise it will be halved */
92  float gamma; /* lower gamma, more contrast, higher gamma, more range */
93  int fps; /* the required fps is so strict, so it's enough to be int, but 24000/1001 etc cannot be encoded */
94  int count; /* fps * count = transform rate */
95 } ShowCQTContext;
96 
97 #define OFFSET(x) offsetof(ShowCQTContext, x)
98 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
99 
100 static const AVOption showcqt_options[] = {
101  { "volume", "set volume", OFFSET(volume), AV_OPT_TYPE_STRING, { .str = "16" }, CHAR_MIN, CHAR_MAX, FLAGS },
102  { "tlength", "set transform length", OFFSET(tlength), AV_OPT_TYPE_STRING, { .str = TLENGTH_DEFAULT }, CHAR_MIN, CHAR_MAX, FLAGS },
103  { "timeclamp", "set timeclamp", OFFSET(timeclamp), AV_OPT_TYPE_DOUBLE, { .dbl = 0.17 }, 0.1, 1.0, FLAGS },
104  { "coeffclamp", "set coeffclamp", OFFSET(coeffclamp), AV_OPT_TYPE_FLOAT, { .dbl = 1 }, 0.1, 10, FLAGS },
105  { "gamma", "set gamma", OFFSET(gamma), AV_OPT_TYPE_FLOAT, { .dbl = 3 }, 1, 7, FLAGS },
106  { "fullhd", "set full HD resolution", OFFSET(fullhd), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS },
107  { "fps", "set video fps", OFFSET(fps), AV_OPT_TYPE_INT, { .i64 = 25 }, 10, 100, FLAGS },
108  { "count", "set number of transform per frame", OFFSET(count), AV_OPT_TYPE_INT, { .i64 = 6 }, 1, 30, FLAGS },
109  { "fontfile", "set font file", OFFSET(fontfile), AV_OPT_TYPE_STRING, { .str = NULL }, CHAR_MIN, CHAR_MAX, FLAGS },
110  { "fontcolor", "set font color", OFFSET(fontcolor), AV_OPT_TYPE_STRING, { .str = FONTCOLOR_DEFAULT }, CHAR_MIN, CHAR_MAX, FLAGS },
111  { NULL }
112 };
113 
114 AVFILTER_DEFINE_CLASS(showcqt);
115 
116 static av_cold void uninit(AVFilterContext *ctx)
117 {
118  int k;
119 
120  ShowCQTContext *s = ctx->priv;
121  av_fft_end(s->fft_context);
122  s->fft_context = NULL;
123  for (k = 0; k < VIDEO_WIDTH; k++)
124  av_freep(&s->coeffs[k]);
125  av_freep(&s->fft_data);
126  av_freep(&s->fft_result_left);
127  av_freep(&s->fft_result_right);
128  av_freep(&s->coeff_sort);
129  av_freep(&s->spectogram);
130  av_freep(&s->font_alpha);
131  av_frame_free(&s->outpicref);
132 }
133 
134 static int query_formats(AVFilterContext *ctx)
135 {
136  AVFilterFormats *formats = NULL;
137  AVFilterChannelLayouts *layouts = NULL;
138  AVFilterLink *inlink = ctx->inputs[0];
139  AVFilterLink *outlink = ctx->outputs[0];
140  static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_NONE };
141  static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_RGB24, AV_PIX_FMT_NONE };
142  static const int64_t channel_layouts[] = { AV_CH_LAYOUT_STEREO, AV_CH_LAYOUT_STEREO_DOWNMIX, -1 };
143  static const int samplerates[] = { 44100, 48000, -1 };
144 
145  /* set input audio formats */
146  formats = ff_make_format_list(sample_fmts);
147  if (!formats)
148  return AVERROR(ENOMEM);
149  ff_formats_ref(formats, &inlink->out_formats);
150 
151  layouts = avfilter_make_format64_list(channel_layouts);
152  if (!layouts)
153  return AVERROR(ENOMEM);
154  ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts);
155 
156  formats = ff_make_format_list(samplerates);
157  if (!formats)
158  return AVERROR(ENOMEM);
159  ff_formats_ref(formats, &inlink->out_samplerates);
160 
161  /* set output video format */
162  formats = ff_make_format_list(pix_fmts);
163  if (!formats)
164  return AVERROR(ENOMEM);
165  ff_formats_ref(formats, &outlink->in_formats);
166 
167  return 0;
168 }
169 
170 #if CONFIG_LIBFREETYPE
171 static void load_freetype_font(AVFilterContext *ctx)
172 {
173  static const char str[] = "EF G A BC D ";
174  ShowCQTContext *s = ctx->priv;
175  FT_Library lib = NULL;
176  FT_Face face = NULL;
177  int video_scale = s->fullhd ? 2 : 1;
178  int video_width = (VIDEO_WIDTH/2) * video_scale;
179  int font_height = (FONT_HEIGHT/2) * video_scale;
180  int font_width = 8 * video_scale;
181  int font_repeat = font_width * 12;
182  int linear_hori_advance = font_width * 65536;
183  int non_monospace_warning = 0;
184  int x;
185 
186  s->font_alpha = NULL;
187 
188  if (!s->fontfile)
189  return;
190 
191  if (FT_Init_FreeType(&lib))
192  goto fail;
193 
194  if (FT_New_Face(lib, s->fontfile, 0, &face))
195  goto fail;
196 
197  if (FT_Set_Char_Size(face, 16*64, 0, 0, 0))
198  goto fail;
199 
200  if (FT_Load_Char(face, 'A', FT_LOAD_RENDER))
201  goto fail;
202 
203  if (FT_Set_Char_Size(face, 16*64 * linear_hori_advance / face->glyph->linearHoriAdvance, 0, 0, 0))
204  goto fail;
205 
206  s->font_alpha = av_malloc(font_height * video_width);
207  if (!s->font_alpha)
208  goto fail;
209 
210  memset(s->font_alpha, 0, font_height * video_width);
211 
212  for (x = 0; x < 12; x++) {
213  int sx, sy, rx, bx, by, dx, dy;
214 
215  if (str[x] == ' ')
216  continue;
217 
218  if (FT_Load_Char(face, str[x], FT_LOAD_RENDER))
219  goto fail;
220 
221  if (face->glyph->advance.x != font_width*64 && !non_monospace_warning) {
222  av_log(ctx, AV_LOG_WARNING, "Font is not monospace\n");
223  non_monospace_warning = 1;
224  }
225 
226  sy = font_height - 4*video_scale - face->glyph->bitmap_top;
227  for (rx = 0; rx < 10; rx++) {
228  sx = rx * font_repeat + x * font_width + face->glyph->bitmap_left;
229  for (by = 0; by < face->glyph->bitmap.rows; by++) {
230  dy = by + sy;
231  if (dy < 0)
232  continue;
233  if (dy >= font_height)
234  break;
235 
236  for (bx = 0; bx < face->glyph->bitmap.width; bx++) {
237  dx = bx + sx;
238  if (dx < 0)
239  continue;
240  if (dx >= video_width)
241  break;
242  s->font_alpha[dy*video_width+dx] = face->glyph->bitmap.buffer[by*face->glyph->bitmap.width+bx];
243  }
244  }
245  }
246  }
247 
248  FT_Done_Face(face);
249  FT_Done_FreeType(lib);
250  return;
251 
252  fail:
253  av_log(ctx, AV_LOG_WARNING, "Error while loading freetype font, using default font instead\n");
254  FT_Done_Face(face);
255  FT_Done_FreeType(lib);
256  av_freep(&s->font_alpha);
257  return;
258 }
259 #endif
260 
261 static double a_weighting(void *p, double f)
262 {
263  double ret = 12200.0*12200.0 * (f*f*f*f);
264  ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0) *
265  sqrt((f*f + 107.7*107.7) * (f*f + 737.9*737.9));
266  return ret;
267 }
268 
269 static double b_weighting(void *p, double f)
270 {
271  double ret = 12200.0*12200.0 * (f*f*f);
272  ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0) * sqrt(f*f + 158.5*158.5);
273  return ret;
274 }
275 
276 static double c_weighting(void *p, double f)
277 {
278  double ret = 12200.0*12200.0 * (f*f);
279  ret /= (f*f + 20.6*20.6) * (f*f + 12200.0*12200.0);
280  return ret;
281 }
282 
283 static double midi(void *p, double f)
284 {
285  return log2(f/440.0) * 12.0 + 69.0;
286 }
287 
288 static double r_func(void *p, double x)
289 {
290  x = av_clipd(x, 0.0, 1.0);
291  return (int)(x*255.0+0.5) << 16;
292 }
293 
294 static double g_func(void *p, double x)
295 {
296  x = av_clipd(x, 0.0, 1.0);
297  return (int)(x*255.0+0.5) << 8;
298 }
299 
300 static double b_func(void *p, double x)
301 {
302  x = av_clipd(x, 0.0, 1.0);
303  return (int)(x*255.0+0.5);
304 }
305 
306 static inline int qsort_sparsecoeff(const SparseCoeff *a, const SparseCoeff *b)
307 {
308  if (fabsf(a->value) >= fabsf(b->value))
309  return 1;
310  else
311  return -1;
312 }
313 
314 static int config_output(AVFilterLink *outlink)
315 {
316  AVFilterContext *ctx = outlink->src;
317  AVFilterLink *inlink = ctx->inputs[0];
318  ShowCQTContext *s = ctx->priv;
319  AVExpr *tlength_expr = NULL, *volume_expr = NULL, *fontcolor_expr = NULL;
320  uint8_t *fontcolor_value = s->fontcolor_value;
321  static const char * const expr_vars[] = { "timeclamp", "tc", "frequency", "freq", "f", NULL };
322  static const char * const expr_func_names[] = { "a_weighting", "b_weighting", "c_weighting", NULL };
323  static const char * const expr_fontcolor_func_names[] = { "midi", "r", "g", "b", NULL };
324  static double (* const expr_funcs[])(void *, double) = { a_weighting, b_weighting, c_weighting, NULL };
325  static double (* const expr_fontcolor_funcs[])(void *, double) = { midi, r_func, g_func, b_func, NULL };
326  int fft_len, k, x, y, ret;
327  int num_coeffs = 0;
328  int rate = inlink->sample_rate;
329  double max_len = rate * (double) s->timeclamp;
330  int64_t start_time, end_time;
331  int video_scale = s->fullhd ? 2 : 1;
332  int video_width = (VIDEO_WIDTH/2) * video_scale;
333  int video_height = (VIDEO_HEIGHT/2) * video_scale;
334  int spectogram_height = (SPECTOGRAM_HEIGHT/2) * video_scale;
335 
336  s->fft_bits = ceil(log2(max_len));
337  fft_len = 1 << s->fft_bits;
338 
339  if (rate % (s->fps * s->count)) {
340  av_log(ctx, AV_LOG_ERROR, "Rate (%u) is not divisible by fps*count (%u*%u)\n", rate, s->fps, s->count);
341  return AVERROR(EINVAL);
342  }
343 
344  s->fft_data = av_malloc_array(fft_len, sizeof(*s->fft_data));
345  s->coeff_sort = av_malloc_array(fft_len, sizeof(*s->coeff_sort));
346  s->fft_result_left = av_malloc_array(fft_len, sizeof(*s->fft_result_left));
347  s->fft_result_right = av_malloc_array(fft_len, sizeof(*s->fft_result_right));
348  s->fft_context = av_fft_init(s->fft_bits, 0);
349 
350  if (!s->fft_data || !s->coeff_sort || !s->fft_result_left || !s->fft_result_right || !s->fft_context)
351  return AVERROR(ENOMEM);
352 
353 #if CONFIG_LIBFREETYPE
354  load_freetype_font(ctx);
355 #else
356  if (s->fontfile)
357  av_log(ctx, AV_LOG_WARNING, "Freetype is not available, ignoring fontfile option\n");
358  s->font_alpha = NULL;
359 #endif
360 
361  av_log(ctx, AV_LOG_INFO, "Calculating spectral kernel, please wait\n");
362  start_time = av_gettime_relative();
363  ret = av_expr_parse(&tlength_expr, s->tlength, expr_vars, NULL, NULL, NULL, NULL, 0, ctx);
364  if (ret < 0)
365  goto eval_error;
366 
367  ret = av_expr_parse(&volume_expr, s->volume, expr_vars, expr_func_names,
368  expr_funcs, NULL, NULL, 0, ctx);
369  if (ret < 0)
370  goto eval_error;
371 
372  ret = av_expr_parse(&fontcolor_expr, s->fontcolor, expr_vars, expr_fontcolor_func_names,
373  expr_fontcolor_funcs, NULL, NULL, 0, ctx);
374  if (ret < 0)
375  goto eval_error;
376 
377  for (k = 0; k < VIDEO_WIDTH; k++) {
378  int hlen = fft_len >> 1;
379  float total = 0;
380  float partial = 0;
381  double freq = BASE_FREQ * exp2(k * (1.0/192.0));
382  double tlen, tlength, volume;
383  double expr_vars_val[] = { s->timeclamp, s->timeclamp, freq, freq, freq, 0 };
384  /* a window function from Albert H. Nuttall,
385  * "Some Windows with Very Good Sidelobe Behavior"
386  * -93.32 dB peak sidelobe and 18 dB/octave asymptotic decay
387  * coefficient normalized to a0 = 1 */
388  double a0 = 0.355768;
389  double a1 = 0.487396/a0;
390  double a2 = 0.144232/a0;
391  double a3 = 0.012604/a0;
392  double sv_step, cv_step, sv, cv;
393  double sw_step, cw_step, sw, cw, w;
394 
395  tlength = av_expr_eval(tlength_expr, expr_vars_val, NULL);
396  if (isnan(tlength)) {
397  av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is nan, setting it to %g\n", freq, s->timeclamp);
398  tlength = s->timeclamp;
399  } else if (tlength < TLENGTH_MIN) {
400  av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is %g, setting it to %g\n", freq, tlength, TLENGTH_MIN);
401  tlength = TLENGTH_MIN;
402  } else if (tlength > s->timeclamp) {
403  av_log(ctx, AV_LOG_WARNING, "at freq %g: tlength is %g, setting it to %g\n", freq, tlength, s->timeclamp);
404  tlength = s->timeclamp;
405  }
406 
407  volume = FFABS(av_expr_eval(volume_expr, expr_vars_val, NULL));
408  if (isnan(volume)) {
409  av_log(ctx, AV_LOG_WARNING, "at freq %g: volume is nan, setting it to 0\n", freq);
410  volume = VOLUME_MIN;
411  } else if (volume < VOLUME_MIN) {
412  volume = VOLUME_MIN;
413  } else if (volume > VOLUME_MAX) {
414  av_log(ctx, AV_LOG_WARNING, "at freq %g: volume is %g, setting it to %g\n", freq, volume, VOLUME_MAX);
415  volume = VOLUME_MAX;
416  }
417 
418  if (s->fullhd || !(k & 1)) {
419  int fontcolor = av_expr_eval(fontcolor_expr, expr_vars_val, NULL);
420  fontcolor_value[0] = (fontcolor >> 16) & 0xFF;
421  fontcolor_value[1] = (fontcolor >> 8) & 0xFF;
422  fontcolor_value[2] = fontcolor & 0xFF;
423  fontcolor_value += 3;
424  }
425 
426  tlen = tlength * rate;
427  s->fft_data[0].re = 0;
428  s->fft_data[0].im = 0;
429  s->fft_data[hlen].re = (1.0 + a1 + a2 + a3) * (1.0/tlen) * volume * (1.0/fft_len);
430  s->fft_data[hlen].im = 0;
431  sv_step = sv = sin(2.0*M_PI*freq*(1.0/rate));
432  cv_step = cv = cos(2.0*M_PI*freq*(1.0/rate));
433  /* also optimizing window func */
434  sw_step = sw = sin(2.0*M_PI*(1.0/tlen));
435  cw_step = cw = cos(2.0*M_PI*(1.0/tlen));
436  for (x = 1; x < 0.5 * tlen; x++) {
437  double cv_tmp, cw_tmp;
438  double cw2, cw3, sw2;
439 
440  cw2 = cw * cw - sw * sw;
441  sw2 = cw * sw + sw * cw;
442  cw3 = cw * cw2 - sw * sw2;
443  w = (1.0 + a1 * cw + a2 * cw2 + a3 * cw3) * (1.0/tlen) * volume * (1.0/fft_len);
444  s->fft_data[hlen + x].re = w * cv;
445  s->fft_data[hlen + x].im = w * sv;
446  s->fft_data[hlen - x].re = s->fft_data[hlen + x].re;
447  s->fft_data[hlen - x].im = -s->fft_data[hlen + x].im;
448 
449  cv_tmp = cv * cv_step - sv * sv_step;
450  sv = sv * cv_step + cv * sv_step;
451  cv = cv_tmp;
452  cw_tmp = cw * cw_step - sw * sw_step;
453  sw = sw * cw_step + cw * sw_step;
454  cw = cw_tmp;
455  }
456  for (; x < hlen; x++) {
457  s->fft_data[hlen + x].re = 0;
458  s->fft_data[hlen + x].im = 0;
459  s->fft_data[hlen - x].re = 0;
460  s->fft_data[hlen - x].im = 0;
461  }
462  av_fft_permute(s->fft_context, s->fft_data);
463  av_fft_calc(s->fft_context, s->fft_data);
464 
465  for (x = 0; x < fft_len; x++) {
466  s->coeff_sort[x].index = x;
467  s->coeff_sort[x].value = s->fft_data[x].re;
468  }
469 
470  AV_QSORT(s->coeff_sort, fft_len, SparseCoeff, qsort_sparsecoeff);
471  for (x = 0; x < fft_len; x++)
472  total += fabsf(s->coeff_sort[x].value);
473 
474  for (x = 0; x < fft_len; x++) {
475  partial += fabsf(s->coeff_sort[x].value);
476  if (partial > total * s->coeffclamp * COEFF_CLAMP) {
477  s->coeffs_len[k] = fft_len - x;
478  num_coeffs += s->coeffs_len[k];
479  s->coeffs[k] = av_malloc_array(s->coeffs_len[k], sizeof(*s->coeffs[k]));
480  if (!s->coeffs[k]) {
481  ret = AVERROR(ENOMEM);
482  goto eval_error;
483  }
484  for (y = 0; y < s->coeffs_len[k]; y++)
485  s->coeffs[k][y] = s->coeff_sort[x+y];
486  break;
487  }
488  }
489  }
490  av_expr_free(fontcolor_expr);
491  av_expr_free(volume_expr);
492  av_expr_free(tlength_expr);
493  end_time = av_gettime_relative();
494  av_log(ctx, AV_LOG_INFO, "Elapsed time %.6f s (fft_len=%u, num_coeffs=%u)\n", 1e-6 * (end_time-start_time), fft_len, num_coeffs);
495 
496  outlink->w = video_width;
497  outlink->h = video_height;
498 
499  s->req_fullfilled = 0;
500  s->spectogram_index = 0;
501  s->frame_count = 0;
502  s->spectogram_count = 0;
503  s->remaining_fill = fft_len >> 1;
504  memset(s->fft_data, 0, fft_len * sizeof(*s->fft_data));
505 
506  s->outpicref = ff_get_video_buffer(outlink, outlink->w, outlink->h);
507  if (!s->outpicref)
508  return AVERROR(ENOMEM);
509 
510  s->spectogram = av_calloc(spectogram_height, s->outpicref->linesize[0]);
511  if (!s->spectogram)
512  return AVERROR(ENOMEM);
513 
514  outlink->sample_aspect_ratio = av_make_q(1, 1);
515  outlink->time_base = av_make_q(1, s->fps);
516  outlink->frame_rate = av_make_q(s->fps, 1);
517  return 0;
518 
519 eval_error:
520  av_expr_free(fontcolor_expr);
521  av_expr_free(volume_expr);
522  av_expr_free(tlength_expr);
523  return ret;
524 }
525 
526 static int plot_cqt(AVFilterLink *inlink)
527 {
528  AVFilterContext *ctx = inlink->dst;
529  ShowCQTContext *s = ctx->priv;
530  AVFilterLink *outlink = ctx->outputs[0];
531  int fft_len = 1 << s->fft_bits;
532  FFTSample result[VIDEO_WIDTH][4];
533  int x, y, ret = 0;
534  int linesize = s->outpicref->linesize[0];
535  int video_scale = s->fullhd ? 2 : 1;
536  int video_width = (VIDEO_WIDTH/2) * video_scale;
537  int spectogram_height = (SPECTOGRAM_HEIGHT/2) * video_scale;
538  int spectogram_start = (SPECTOGRAM_START/2) * video_scale;
539  int font_height = (FONT_HEIGHT/2) * video_scale;
540 
541  /* real part contains left samples, imaginary part contains right samples */
542  memcpy(s->fft_result_left, s->fft_data, fft_len * sizeof(*s->fft_data));
543  av_fft_permute(s->fft_context, s->fft_result_left);
544  av_fft_calc(s->fft_context, s->fft_result_left);
545 
546  /* separate left and right, (and multiply by 2.0) */
547  s->fft_result_right[0].re = 2.0f * s->fft_result_left[0].im;
548  s->fft_result_right[0].im = 0;
549  s->fft_result_left[0].re = 2.0f * s->fft_result_left[0].re;
550  s->fft_result_left[0].im = 0;
551  for (x = 1; x <= fft_len >> 1; x++) {
552  FFTSample tmpy = s->fft_result_left[fft_len-x].im - s->fft_result_left[x].im;
553 
554  s->fft_result_right[x].re = s->fft_result_left[x].im + s->fft_result_left[fft_len-x].im;
555  s->fft_result_right[x].im = s->fft_result_left[x].re - s->fft_result_left[fft_len-x].re;
556  s->fft_result_right[fft_len-x].re = s->fft_result_right[x].re;
557  s->fft_result_right[fft_len-x].im = -s->fft_result_right[x].im;
558 
559  s->fft_result_left[x].re = s->fft_result_left[x].re + s->fft_result_left[fft_len-x].re;
560  s->fft_result_left[x].im = tmpy;
561  s->fft_result_left[fft_len-x].re = s->fft_result_left[x].re;
562  s->fft_result_left[fft_len-x].im = -s->fft_result_left[x].im;
563  }
564 
565  /* calculating cqt */
566  for (x = 0; x < VIDEO_WIDTH; x++) {
567  int u;
568  float g = 1.0f / s->gamma;
569  FFTComplex l = {0,0};
570  FFTComplex r = {0,0};
571 
572  for (u = 0; u < s->coeffs_len[x]; u++) {
573  FFTSample value = s->coeffs[x][u].value;
574  int index = s->coeffs[x][u].index;
575  l.re += value * s->fft_result_left[index].re;
576  l.im += value * s->fft_result_left[index].im;
577  r.re += value * s->fft_result_right[index].re;
578  r.im += value * s->fft_result_right[index].im;
579  }
580  /* result is power, not amplitude */
581  result[x][0] = l.re * l.re + l.im * l.im;
582  result[x][2] = r.re * r.re + r.im * r.im;
583  result[x][1] = 0.5f * (result[x][0] + result[x][2]);
584  result[x][3] = result[x][1];
585  result[x][0] = 255.0f * powf(FFMIN(1.0f,result[x][0]), g);
586  result[x][1] = 255.0f * powf(FFMIN(1.0f,result[x][1]), g);
587  result[x][2] = 255.0f * powf(FFMIN(1.0f,result[x][2]), g);
588  }
589 
590  if (!s->fullhd) {
591  for (x = 0; x < video_width; x++) {
592  result[x][0] = 0.5f * (result[2*x][0] + result[2*x+1][0]);
593  result[x][1] = 0.5f * (result[2*x][1] + result[2*x+1][1]);
594  result[x][2] = 0.5f * (result[2*x][2] + result[2*x+1][2]);
595  result[x][3] = 0.5f * (result[2*x][3] + result[2*x+1][3]);
596  }
597  }
598 
599  for (x = 0; x < video_width; x++) {
600  s->spectogram[s->spectogram_index*linesize + 3*x] = result[x][0] + 0.5f;
601  s->spectogram[s->spectogram_index*linesize + 3*x + 1] = result[x][1] + 0.5f;
602  s->spectogram[s->spectogram_index*linesize + 3*x + 2] = result[x][2] + 0.5f;
603  }
604 
605  /* drawing */
606  if (!s->spectogram_count) {
607  uint8_t *data = (uint8_t*) s->outpicref->data[0];
608  float rcp_result[VIDEO_WIDTH];
609  int total_length = linesize * spectogram_height;
610  int back_length = linesize * s->spectogram_index;
611 
612  for (x = 0; x < video_width; x++)
613  rcp_result[x] = 1.0f / (result[x][3]+0.0001f);
614 
615  /* drawing bar */
616  for (y = 0; y < spectogram_height; y++) {
617  float height = (spectogram_height - y) * (1.0f/spectogram_height);
618  uint8_t *lineptr = data + y * linesize;
619  for (x = 0; x < video_width; x++) {
620  float mul;
621  if (result[x][3] <= height) {
622  *lineptr++ = 0;
623  *lineptr++ = 0;
624  *lineptr++ = 0;
625  } else {
626  mul = (result[x][3] - height) * rcp_result[x];
627  *lineptr++ = mul * result[x][0] + 0.5f;
628  *lineptr++ = mul * result[x][1] + 0.5f;
629  *lineptr++ = mul * result[x][2] + 0.5f;
630  }
631  }
632  }
633 
634  /* drawing font */
635  if (s->font_alpha) {
636  for (y = 0; y < font_height; y++) {
637  uint8_t *lineptr = data + (spectogram_height + y) * linesize;
638  uint8_t *spectogram_src = s->spectogram + s->spectogram_index * linesize;
639  uint8_t *fontcolor_value = s->fontcolor_value;
640  for (x = 0; x < video_width; x++) {
641  uint8_t alpha = s->font_alpha[y*video_width+x];
642  lineptr[3*x] = (spectogram_src[3*x] * (255-alpha) + fontcolor_value[0] * alpha + 255) >> 8;
643  lineptr[3*x+1] = (spectogram_src[3*x+1] * (255-alpha) + fontcolor_value[1] * alpha + 255) >> 8;
644  lineptr[3*x+2] = (spectogram_src[3*x+2] * (255-alpha) + fontcolor_value[2] * alpha + 255) >> 8;
645  fontcolor_value += 3;
646  }
647  }
648  } else {
649  for (y = 0; y < font_height; y++) {
650  uint8_t *lineptr = data + (spectogram_height + y) * linesize;
651  memcpy(lineptr, s->spectogram + s->spectogram_index * linesize, video_width*3);
652  }
653  for (x = 0; x < video_width; x += video_width/10) {
654  int u;
655  static const char str[] = "EF G A BC D ";
656  uint8_t *startptr = data + spectogram_height * linesize + x * 3;
657  for (u = 0; str[u]; u++) {
658  int v;
659  for (v = 0; v < 16; v++) {
660  uint8_t *p = startptr + v * linesize * video_scale + 8 * 3 * u * video_scale;
661  int ux = x + 8 * u * video_scale;
662  int mask;
663  for (mask = 0x80; mask; mask >>= 1) {
664  if (mask & avpriv_vga16_font[str[u] * 16 + v]) {
665  p[0] = s->fontcolor_value[3*ux];
666  p[1] = s->fontcolor_value[3*ux+1];
667  p[2] = s->fontcolor_value[3*ux+2];
668  if (video_scale == 2) {
669  p[linesize] = p[0];
670  p[linesize+1] = p[1];
671  p[linesize+2] = p[2];
672  p[3] = p[linesize+3] = s->fontcolor_value[3*ux+3];
673  p[4] = p[linesize+4] = s->fontcolor_value[3*ux+4];
674  p[5] = p[linesize+5] = s->fontcolor_value[3*ux+5];
675  }
676  }
677  p += 3 * video_scale;
678  ux += video_scale;
679  }
680  }
681  }
682  }
683  }
684 
685  /* drawing spectogram/sonogram */
686  data += spectogram_start * linesize;
687  memcpy(data, s->spectogram + s->spectogram_index*linesize, total_length - back_length);
688 
689  data += total_length - back_length;
690  if (back_length)
691  memcpy(data, s->spectogram, back_length);
692 
693  s->outpicref->pts = s->frame_count;
694  ret = ff_filter_frame(outlink, av_frame_clone(s->outpicref));
695  s->req_fullfilled = 1;
696  s->frame_count++;
697  }
698  s->spectogram_count = (s->spectogram_count + 1) % s->count;
699  s->spectogram_index = (s->spectogram_index + spectogram_height - 1) % spectogram_height;
700  return ret;
701 }
702 
703 static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
704 {
705  AVFilterContext *ctx = inlink->dst;
706  ShowCQTContext *s = ctx->priv;
707  int step = inlink->sample_rate / (s->fps * s->count);
708  int fft_len = 1 << s->fft_bits;
709  int remaining;
710  float *audio_data;
711 
712  if (!insamples) {
713  while (s->remaining_fill < (fft_len >> 1)) {
714  int ret, x;
715  memset(&s->fft_data[fft_len - s->remaining_fill], 0, sizeof(*s->fft_data) * s->remaining_fill);
716  ret = plot_cqt(inlink);
717  if (ret < 0)
718  return ret;
719  for (x = 0; x < (fft_len-step); x++)
720  s->fft_data[x] = s->fft_data[x+step];
721  s->remaining_fill += step;
722  }
723  return AVERROR(EOF);
724  }
725 
726  remaining = insamples->nb_samples;
727  audio_data = (float*) insamples->data[0];
728 
729  while (remaining) {
730  if (remaining >= s->remaining_fill) {
731  int i = insamples->nb_samples - remaining;
732  int j = fft_len - s->remaining_fill;
733  int m, ret;
734  for (m = 0; m < s->remaining_fill; m++) {
735  s->fft_data[j+m].re = audio_data[2*(i+m)];
736  s->fft_data[j+m].im = audio_data[2*(i+m)+1];
737  }
738  ret = plot_cqt(inlink);
739  if (ret < 0) {
740  av_frame_free(&insamples);
741  return ret;
742  }
743  remaining -= s->remaining_fill;
744  for (m = 0; m < fft_len-step; m++)
745  s->fft_data[m] = s->fft_data[m+step];
746  s->remaining_fill = step;
747  } else {
748  int i = insamples->nb_samples - remaining;
749  int j = fft_len - s->remaining_fill;
750  int m;
751  for (m = 0; m < remaining; m++) {
752  s->fft_data[m+j].re = audio_data[2*(i+m)];
753  s->fft_data[m+j].im = audio_data[2*(i+m)+1];
754  }
755  s->remaining_fill -= remaining;
756  remaining = 0;
757  }
758  }
759  av_frame_free(&insamples);
760  return 0;
761 }
762 
763 static int request_frame(AVFilterLink *outlink)
764 {
765  ShowCQTContext *s = outlink->src->priv;
766  AVFilterLink *inlink = outlink->src->inputs[0];
767  int ret;
768 
769  s->req_fullfilled = 0;
770  do {
771  ret = ff_request_frame(inlink);
772  } while (!s->req_fullfilled && ret >= 0);
773 
774  if (ret == AVERROR_EOF && s->outpicref)
775  filter_frame(inlink, NULL);
776  return ret;
777 }
778 
779 static const AVFilterPad showcqt_inputs[] = {
780  {
781  .name = "default",
782  .type = AVMEDIA_TYPE_AUDIO,
783  .filter_frame = filter_frame,
784  },
785  { NULL }
786 };
787 
788 static const AVFilterPad showcqt_outputs[] = {
789  {
790  .name = "default",
791  .type = AVMEDIA_TYPE_VIDEO,
792  .config_props = config_output,
793  .request_frame = request_frame,
794  },
795  { NULL }
796 };
797 
798 AVFilter ff_avf_showcqt = {
799  .name = "showcqt",
800  .description = NULL_IF_CONFIG_SMALL("Convert input audio to a CQT (Constant Q Transform) spectrum video output."),
801  .uninit = uninit,
802  .query_formats = query_formats,
803  .priv_size = sizeof(ShowCQTContext),
804  .inputs = showcqt_inputs,
805  .outputs = showcqt_outputs,
806  .priv_class = &showcqt_class,
807 };
Generated on Fri Dec 5 2014 04:42:07 for FFmpeg by   doxygen 1.8.2