From 4acd08be6c4f39736179a3d90fd56b508e42ff6d Mon Sep 17 00:00:00 2001
From: Lynne <dev@lynne.ee>
Date: Sat, 18 Feb 2023 13:14:31 +0100
Subject: [PATCH] ffplay: port to lavu/tx

---
 fftools/ffplay.c | 42 +++++++++++++++++++++++++++---------------
 1 file changed, 27 insertions(+), 15 deletions(-)

diff --git a/fftools/ffplay.c b/fftools/ffplay.c
index 5212ad053e..006da7ab57 100644
--- a/fftools/ffplay.c
+++ b/fftools/ffplay.c
@@ -47,7 +47,7 @@
 #include "libavdevice/avdevice.h"
 #include "libswscale/swscale.h"
 #include "libavutil/opt.h"
-#include "libavcodec/avfft.h"
+#include "libavutil/tx.h"
 #include "libswresample/swresample.h"
 
 #include "libavfilter/avfilter.h"
@@ -262,9 +262,11 @@ typedef struct VideoState {
     int16_t sample_array[SAMPLE_ARRAY_SIZE];
     int sample_array_index;
     int last_i_start;
-    RDFTContext *rdft;
+    AVTXContext *rdft;
+    av_tx_fn rdft_fn;
     int rdft_bits;
-    FFTSample *rdft_data;
+    float *real_data;
+    AVComplexFloat *rdft_data;
     int xpos;
     double last_vis_time;
     SDL_Texture *vis_texture;
@@ -1120,6 +1122,7 @@ static void video_audio_display(VideoState *s)
             fill_rectangle(s->xleft, y, s->width, 1);
         }
     } else {
+        int err = 0;
         if (realloc_texture(&s->vis_texture, SDL_PIXELFORMAT_ARGB8888, s->width, s->height, SDL_BLENDMODE_NONE, 1) < 0)
             return;
 
@@ -1127,31 +1130,39 @@ static void video_audio_display(VideoState *s)
             s->xpos = 0;
         nb_display_channels= FFMIN(nb_display_channels, 2);
         if (rdft_bits != s->rdft_bits) {
-            av_rdft_end(s->rdft);
-            av_free(s->rdft_data);
-            s->rdft = av_rdft_init(rdft_bits, DFT_R2C);
+            const float rdft_scale = 1.0;
+            av_tx_uninit(&s->rdft);
+            av_freep(&s->real_data);
+            av_freep(&s->rdft_data);
             s->rdft_bits = rdft_bits;
-            s->rdft_data = av_malloc_array(nb_freq, 4 *sizeof(*s->rdft_data));
+            s->real_data = av_malloc_array(nb_freq, 4 *sizeof(*s->real_data));
+            s->rdft_data = av_malloc_array(nb_freq + 1, 2 *sizeof(*s->rdft_data));
+            err = av_tx_init(&s->rdft, &s->rdft_fn, AV_TX_FLOAT_RDFT,
+                             0, 1 << rdft_bits, &rdft_scale, 0);
         }
-        if (!s->rdft || !s->rdft_data){
+        if (err < 0 || !s->rdft_data) {
             av_log(NULL, AV_LOG_ERROR, "Failed to allocate buffers for RDFT, switching to waves display\n");
             s->show_mode = SHOW_MODE_WAVES;
         } else {
-            FFTSample *data[2];
+            float *data_in[2];
+            AVComplexFloat *data[2];
             SDL_Rect rect = {.x = s->xpos, .y = 0, .w = 1, .h = s->height};
             uint32_t *pixels;
             int pitch;
             for (ch = 0; ch < nb_display_channels; ch++) {
-                data[ch] = s->rdft_data + 2 * nb_freq * ch;
+                data_in[ch] = s->real_data + 2 * nb_freq * ch;
+                data[ch] = s->rdft_data + nb_freq * ch;
                 i = i_start + ch;
                 for (x = 0; x < 2 * nb_freq; x++) {
                     double w = (x-nb_freq) * (1.0 / nb_freq);
-                    data[ch][x] = s->sample_array[i] * (1.0 - w * w);
+                    data_in[ch][x] = s->sample_array[i] * (1.0 - w * w);
                     i += channels;
                     if (i >= SAMPLE_ARRAY_SIZE)
                         i -= SAMPLE_ARRAY_SIZE;
                 }
-                av_rdft_calc(s->rdft, data[ch]);
+                s->rdft_fn(s->rdft, data[ch], data_in[ch], sizeof(float));
+                data[ch][0].im = data[ch][nb_freq].re;
+                data[ch][nb_freq].re = 0;
             }
             /* Least efficient way to do this, we should of course
              * directly access it but it is more than fast enough. */
@@ -1160,8 +1171,8 @@ static void video_audio_display(VideoState *s)
                 pixels += pitch * s->height;
                 for (y = 0; y < s->height; y++) {
                     double w = 1 / sqrt(nb_freq);
-                    int a = sqrt(w * sqrt(data[0][2 * y + 0] * data[0][2 * y + 0] + data[0][2 * y + 1] * data[0][2 * y + 1]));
-                    int b = (nb_display_channels == 2 ) ? sqrt(w * hypot(data[1][2 * y + 0], data[1][2 * y + 1]))
+                    int a = sqrt(w * sqrt(data[0][y].re * data[0][y].re + data[0][y].im * data[0][y].im));
+                    int b = (nb_display_channels == 2 ) ? sqrt(w * hypot(data[1][y].re, data[1][y].im))
                                                         : a;
                     a = FFMIN(a, 255);
                     b = FFMIN(b, 255);
@@ -1197,7 +1208,8 @@ static void stream_component_close(VideoState *is, int stream_index)
         is->audio_buf = NULL;
 
         if (is->rdft) {
-            av_rdft_end(is->rdft);
+            av_tx_uninit(&is->rdft);
+            av_freep(&is->real_data);
             av_freep(&is->rdft_data);
             is->rdft = NULL;
             is->rdft_bits = 0;