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• aarch64 : vp9 : Add NEON itxfm routines

  13 novembre 2016, par Martin Storsjö

  aarch64 : vp9 : Add NEON itxfm routines
  This work is sponsored by, and copyright, Google.
  These are ported from the ARM version ; thanks to the larger
  
  amount of registers available, we can do the 16x16 and 32x32
  
  transforms in slices 8 pixels wide instead of 4. This gives
  
  a speedup of around 1.4x compared to the 32 bit version.
  The fact that aarch64 doesn’t have the same d/q register
  
  aliasing makes some of the macros quite a bit simpler as well.
  Examples of runtimes vs the 32 bit version, on a Cortex A53 :
  
                                         ARM  AArch64
  
  vp9_inv_adst_adst_4x4_add_neon :       90.0     87.7
  
  vp9_inv_adst_adst_8x8_add_neon :      400.0    354.7
  
  vp9_inv_adst_adst_16x16_add_neon :   2526.5   1827.2
  
  vp9_inv_dct_dct_4x4_add_neon :         74.0     72.7
  
  vp9_inv_dct_dct_8x8_add_neon :        271.0    256.7
  
  vp9_inv_dct_dct_16x16_add_neon :     1960.7   1372.7
  
  vp9_inv_dct_dct_32x32_add_neon :    11988.9   8088.3
  
  vp9_inv_wht_wht_4x4_add_neon :         63.0     57.7
  The speedup vs C code (2-4x) is smaller than in the 32 bit case,
  
  mostly because the C code ends up significantly faster (around
  
  1.6x faster, with GCC 5.4) when built for aarch64.
  Examples of runtimes vs C on a Cortex A57 (for a slightly older version
  
  of the patch) :
  
                                  A57 gcc-5.3   neon
  
  vp9_inv_adst_adst_4x4_add_neon :       152.2   60.0
  
  vp9_inv_adst_adst_8x8_add_neon :       948.2  288.0
  
  vp9_inv_adst_adst_16x16_add_neon :    4830.4 1380.5
  
  vp9_inv_dct_dct_4x4_add_neon :         153.0   58.6
  
  vp9_inv_dct_dct_8x8_add_neon :         789.2  180.2
  
  vp9_inv_dct_dct_16x16_add_neon :      3639.6  917.1
  
  vp9_inv_dct_dct_32x32_add_neon :     20462.1 4985.0
  
  vp9_inv_wht_wht_4x4_add_neon :          91.0   49.8
  The asm is around factor 3-4 faster than C on the cortex-a57 and the asm
  
  is around 30-50% faster on the a57 compared to the a53.
  Signed-off-by : Martin Storsjö <martin@martin.st>
  

  • [DBH] libavcodec/aarch64/Makefile
  • [DBH] libavcodec/aarch64/vp9dsp_init_aarch64.c
  • [DBH] libavcodec/aarch64/vp9itxfm_neon.S

• How to make audio sound better ? (C + FFMpeg audio generation example)

  21 février 2017, par Rella

  So I found this great C FFMpeg official example which I simplified :

  #include 
  
  #include 
  
  #include 
  
  
  
  #ifdef HAVE_AV_CONFIG_H
  
  #undef HAVE_AV_CONFIG_H
  
  #endif
  
  
  
  #include "libavcodec/avcodec.h"
  
  #include "libavutil/mathematics.h"
  
  
  
  #define INBUF_SIZE 4096
  
  #define AUDIO_INBUF_SIZE 20480
  
  #define AUDIO_REFILL_THRESH 4096
  
  
  
  /*
  
   * Audio encoding example
  
   */
  
  static void audio_encode_example(const char *filename)
  
  {
  
      AVCodec *codec;
  
      AVCodecContext *c= NULL;
  
      int frame_size, i, j, out_size, outbuf_size;
  
      FILE *f;
  
      short *samples;
  
      float t, tincr;
  
      uint8_t *outbuf;
  
  
  
      printf("Audio encoding\n");
  
  
  
      /* find the MP2 encoder */
  
      codec = avcodec_find_encoder(CODEC_ID_MP2);
  
      if (!codec) {
  
          fprintf(stderr, "codec not found\n");
  
          exit(1);
  
      }
  
  
  
      c= avcodec_alloc_context();
  
  
  
      /* put sample parameters */
  
      c->bit_rate = 64000;
  
      c->sample_rate = 44100;
  
      c->channels = 2;
  
  
  
      /* open it */
  
      if (avcodec_open(c, codec) < 0) {
  
          fprintf(stderr, "could not open codec\n");
  
          exit(1);
  
      }
  
  
  
      /* the codec gives us the frame size, in samples */
  
      frame_size = c->frame_size;
  
      samples = malloc(frame_size * 2 * c->channels);
  
      outbuf_size = 10000;
  
      outbuf = malloc(outbuf_size);
  
  
  
      f = fopen(filename, "wb");
  
      if (!f) {
  
          fprintf(stderr, "could not open %s\n", filename);
  
          exit(1);
  
      }
  
  
  
      /* encode a single tone sound */
  
      t = 0;
  
      tincr = 2 * M_PI * 440.0 / c->sample_rate;
  
      for(i=0;i<200;i++) {
  
          for(j=0;j* encode the samples */
  
          out_size = avcodec_encode_audio(c, outbuf, outbuf_size, samples);
  
          fwrite(outbuf, 1, out_size, f);
  
      }
  
      fclose(f);
  
      free(outbuf);
  
      free(samples);
  
  
  
      avcodec_close(c);
  
      av_free(c);
  
  }
  
  
  
  int main(int argc, char **argv)
  
  {
  
  
  
      /* must be called before using avcodec lib */
  
      avcodec_init();
  
  
  
      /* register all the codecs */
  
      avcodec_register_all();
  
  
  
      audio_encode_example("test.mp2");
  
  
  
      return 0;
  
  }

  How should it sound like ? May be I don’t get something but it sounds awful =( how to make audio generation sound better/ more interesting/ melodical in a wary shourt way (no special functions just how to change this code to make it sound better) ?

• How to host a react.js ssr on vercel ?

  2 janvier 2024, par UltimateSheepConfusedAtCode

  I want to host a react.js server side rendering because of ffmpeg killing me with SharedArrayBuffer is not defined

  


  I've tried so many hosting service provider like firebase but now I want to host it to Vercel but I don't know how to make it works with react ssr. Can anyone help me ?

  


  When I run 'ssr' command in my machine it's work and ffmpeg is not throwing 'bad memory' or 'SharedArrayBuffer is not defined' but when I run it in vercel build command it stucks but the index.js/server.js is running I know because the main script is running and won't stop so the build is stuck but any solution ? I've search the problem but I guess nobody haven't asked this yet

  


  

  


  and this a code of package.json

  


  {
  "name": "ultimatesheep-vidreverse",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@babel/preset-env": "^7.18.10",
    "@babel/preset-react": "^7.18.6",
    "@babel/register": "^7.18.9",
    "@ffmpeg/core": "^0.11.0",
    "@ffmpeg/ffmpeg": "^0.11.0",
    "@testing-library/jest-dom": "^5.16.5",
    "@testing-library/react": "^13.3.0",
    "@testing-library/user-event": "^13.5.0",
    "bootstrap": "^5.2.0",
    "cors": "^2.8.5",
    "ignore-styles": "^5.0.1",
    "react": "^18.2.0",
    "react-bootstrap": "^2.5.0",
    "react-dom": "^18.2.0",
    "react-scripts": "5.0.1",
    "uuid": "^8.3.2",
    "web-vitals": "^2.1.4"
  },
  "scripts": {
    "start": "react-scripts start",
    "build": "react-scripts build",
    "test": "react-scripts test",
    "eject": "react-scripts eject",
    "ssr": "npm run build && node backend/index.js",
    "deploy": "npm run build && firebase deploy",
    "git" : "git add . && git commit -m 'ahawdaw' && git push -u origin main"
  },
  "eslintConfig": {
    "extends": [
      "react-app",
      "react-app/jest"
    ]
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version"
    ]
  },
  "externals": {
    "react": "React"
  },
  "description": "This project was bootstrapped with [Create React App](https://github.com/facebook/create-react-app).",
  "main": "backend/index.js",
  "keywords": [],
  "author": "",
  "license": "ISC"
}