Fix memory leak and move state entirely into aptdec_t

Standard deviation on a non complete population sample is divided by n-1, not n

.github/ISSUE_TEMPLATE/bug-report.md

@@ -4,7 +4,6 @@ about: Create a bug report to improve aptdec
 title: ''
 labels: bug
 assignees: ''
-
 ---
 
 **Describe the bug**
@@ -17,7 +16,7 @@ Steps to reproduce the behavior.
 A clear description of what you expected to happen.
 
 **Link to audio**
-A link to the audio that caused the problem.
+A link to the audio file that caused the problem (if applicable).
 
 **Build information**
-The commit of aptdec you are running (check with `git rev-parse HEAD`), make sure it's up to date before opening this issue.
+The version of aptdec you are running (check with `git describe --tag`), make sure it's up to date before opening this issue.

.github/workflows/build.yml

@@ -29,16 +29,16 @@ jobs:
     - name: Build and package
       run: cmake --build build -j$(nproc) && cmake --build build --target package
 
-    - name: Upload TGZ package
+    - name: Upload TGZ archive
       uses: actions/upload-artifact@v3
       with:
-          name: TGZ package
+          name: TGZ archive (x86_64-gcc)
           path: build/aptdec_*.tar.gz
 
-    - name: Upload DEB package
+    - name: Upload Debian package
       uses: actions/upload-artifact@v3
       with:
-          name: Debian package
+          name: Debian package (x86_64-gcc)
           path: build/aptdec_*.deb
 
   build_windows:
@@ -56,8 +56,51 @@ jobs:
     - name: Run build script
       run: ./build_windows.sh $BUILD_TYPE
 
-    - name: Upload ZIP package
+    - name: Upload ZIP archive
       uses: actions/upload-artifact@v3
       with:
-          name: ZIP package
+          name: ZIP archive (x86_64-MinGW)
           path: winbuild/aptdec_*.zip
+  
+  build_windows_msvc:
+    runs-on: windows-latest
+
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        submodules: 'recursive'
+        fetch-depth: 0
+
+    - name: Run build script
+      shell: cmd
+      run: '"C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Auxiliary/Build/vcvars64.bat" & build_windows.bat'
+
+    - name: Upload ZIP archive
+      uses: actions/upload-artifact@v3
+      with:
+          name: ZIP archive (x86_64-MSVC)
+          path: winbuild/aptdec_*.zip
+  
+  build_linux_armhf:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v3
+      with:
+        submodules: 'recursive'
+        fetch-depth: 0
+
+    - name: Run build script
+      run: docker run -v $(pwd):/aptdec:z -w /aptdec debian:11 ./build_arm.sh
+
+    - name: Upload Debian package
+      uses: actions/upload-artifact@v3
+      with:
+          name: Debian package (armhf-gcc)
+          path: build/aptdec_*.deb
+
+    - name: Upload TGZ archive
+      uses: actions/upload-artifact@v3
+      with:
+          name: TGZ archive (armhf-gcc)
+          path: build/aptdec_*.tar.gz

.gitignore

@@ -89,3 +89,4 @@ zlib/
 libpng/
 libsndfile-*-win64.zip
 libsndfile-*-win64/
+root/

CMakeLists.txt

@@ -79,13 +79,14 @@ endif()
 install(TARGETS aptdec PUBLIC_HEADER DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/aptdec LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
 # Packaging
-set(CPACK_PACKAGE_VERSION "${VERSION}")
+string(REPLACE v "" CPACK_PACKAGE_VERSION ${VERSION})
+set(CPACK_DEBIAN_PACKAGE_ARCHITECTURE ${CMAKE_SYSTEM_PROCESSOR})
 set(CPACK_PACKAGE_NAME "aptdec")
 set(CPACK_PACKAGE_CONTACT "Xerbo (xerbo@protonmail.com)")
 set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "NOAA APT satellite imagery decoder")
 set(CPACK_PACKAGE_DESCRIPTION "Aptdec is a FOSS library/program that decodes images transmitted by the NOAA POES weather satellites. These satellites transmit constantly (among other things) medium resolution (4km/px) images of the earth over a analog mode called APT.")
 set(CPACK_PACKAGE_FILE_NAME "${CPACK_PACKAGE_NAME}_${CPACK_PACKAGE_VERSION}.${CMAKE_SYSTEM_PROCESSOR}")
-set(CPACK_DEBIAN_PACKAGE_SHLIBDEPS ON)
+set(CPACK_DEBIAN_PACKAGE_DEPENDS "libsndfile1, libpng16-16")
 
 if(WIN32)
     file(GLOB DLLS ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_BINDIR}/*.dll)

UPGRADE_GUIDE.md

@@ -0,0 +1,34 @@
+# Upgrading from aptdec 1.8.0 to 2.0.0
+
+# `aptdec` (now `aptdec-cli`)
+
+## Removed
+
+- The `-d` (output directory) flag
+- The `-g` (gamma) flag
+- Map overlays/MCIR
+- Reading raw PNG images
+
+(Some of these features have been moved into `aptdec_post.py`)
+
+## Changes
+
+- "palettes" are now called "luts"
+- Image type and effects are now full English words (separated by commas) instead of letters
+- Output format of realtime images is now `CURRENT_TIME.png` instead of `CURRENT_TIME-r.png`
+- Channel A/B images include telemetry
+
+## Examples
+
+| v1.8                                  | v2.0.0                                    |
+|---------------------------------------|-------------------------------------------|
+| `aptdec file.wav`                     | `aptdec-cli file.wav`                     |
+| `aptdec -i rt file.wav`               | `aptdec-cli -i raw,thermal file.wav`      |
+| `aptdec -i ab file.wav`               | `aptdec-cli -i a,b -e strip file.wav`     |
+| `aptdec -i p -p palette.png file.wav` | `aptdec-cli -i lut -l lut.png file.wav`   |
+| `aptdec -d out *.wav`                 | `mkdir out; cd out; aptdec-cli ../*.wav`  |
+
+
+# `libapt` (now `libaptdec`)
+
+To avoid confusion with `apt` (the Debian package manager) the name of the aptdec library has been changed to `libaptdec`.

aptdec-cli/main.c

@@ -244,6 +244,7 @@ static int process_file(const char *path, options_t *opts) {
     // Normalize
     int error;
     apt_image_t img = apt_normalize(data, rows, opts->satellite, &error);
+    free(data);
     if (error) {
         error_noexit("Normalization failed");
         return 0;

build_arm.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+# This script only works on Debian Bullseye
+# If you have docker this is trivially easy:
+#   docker run -v $(pwd):/aptdec:z -w /aptdec debian:11 ./build_arm.sh
+
+apt-get update
+apt-get install -y debootstrap cmake gcc-arm-linux-gnueabihf
+
+# Prepare armhf root environment
+if [ ! -d root ]; then
+    debootstrap --keyring=/usr/share/keyrings/debian-archive-keyring.gpg --arch=armhf --include=libsndfile1-dev,libpng-dev --download-only bullseye root http://deb.debian.org/debian/
+    for i in root/var/cache/apt/archives/*.deb; do dpkg -x "$i" root; done
+fi
+
+# Build aptdec
+cmake -B build -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=cmake/toolchain-armhf.cmake -DCMAKE_INSTALL_PREFIX=/aptdec/root
+cmake --build build -j$(nproc)
+cmake --build build --target package

build_windows.bat

@@ -1,36 +1,38 @@
 REM Build using MSVC on Windows
 REM Requires: git, cmake and ninja
+REM You need to run vcvars before running this
 
 REM Build zlib
 IF NOT EXIST zlib (
-    git clone -b v1.2.13 https://github.com/madler/zlib
+    git clone --depth 1 -b v1.2.13 https://github.com/madler/zlib
     cd zlib
-    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DMSVC_TOOLSET_VERSION=190 -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath
-    cmake --build build -j4
+    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath
+    cmake --build build -j%NUMBER_OF_PROCESSORS%
     cmake --build build --target install
     cd ..
 )
 
 REM Build libpng
 IF NOT EXIST libpng (
-    git clone -b v1.6.39 https://github.com/glennrp/libpng
+    git clone --depth 1 -b v1.6.39 https://github.com/glennrp/libpng
     cd libpng
-    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DMSVC_TOOLSET_VERSION=190 -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath -DPNG_STATIC=OFF -DPNG_EXECUTABLES=OFF -DPNG_TESTS=OFF
-    cmake --build build -j4
+    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath -DPNG_STATIC=OFF -DPNG_EXECUTABLES=OFF -DPNG_TESTS=OFF
+    cmake --build build -j%NUMBER_OF_PROCESSORS%
     cmake --build build --target install
     cd ..
 )
 
 REM Build libsndfile, only with WAV support
 IF NOT EXIST libsndfile (
-    git clone -b 1.2.0 https://github.com/libsndfile/libsndfile
+    git clone --depth 1 -b 1.2.0 https://github.com/libsndfile/libsndfile
     cd libsndfile
-    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DMSVC_TOOLSET_VERSION=190 -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath -BUILD_SHARED_LIBS=ON -DBUILD_EXAMPLES=OFF -DBUILD_PROGRAMS=OFF
-    cmake --build build -j4
+    cmake -B build -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath -DBUILD_SHARED_LIBS=ON -DBUILD_EXAMPLES=OFF -DBUILD_PROGRAMS=OFF
+    cmake --build build -j%NUMBER_OF_PROCESSORS%
     cmake --build build --target install
     cd ..
 )
 
 REM Build aptdec
-cmake -B winbuild -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DMSVC_TOOLSET_VERSION=190 -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath
-cmake --build winbuil -j4
+cmake -B winbuild -G Ninja -DCMAKE_C_COMPILER="cl.exe" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=../winpath
+cmake --build winbuild -j%NUMBER_OF_PROCESSORS%
+cmake --build winbuild --target package

cmake/toolchain-armhf.cmake

@@ -0,0 +1,19 @@
+# the name of the target operating system
+SET(CMAKE_SYSTEM_NAME Linux)
+SET(CMAKE_SYSTEM_PROCESSOR armhf)
+
+# which compilers to use for C and C++
+SET(CMAKE_C_COMPILER arm-linux-gnueabihf-gcc)
+SET(CMAKE_CXX_COMPILER arm-linux-gnueabihf-g++)
+
+# here is the target environment located
+SET(CMAKE_FIND_ROOT_PATH /usr/arm-linux-gnueabihf/ ${CMAKE_INSTALL_PREFIX})
+# Hack
+link_directories(${CMAKE_INSTALL_PREFIX}/lib/arm-linux-gnueabihf)
+
+# adjust the default behaviour of the FIND_XXX() commands:
+# search headers and libraries in the target environment, search
+# programs in the host environment
+set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
+set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
+set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

cmake/toolchain-mingw32.cmake

@@ -1,6 +1,6 @@
 # the name of the target operating system
 SET(CMAKE_SYSTEM_NAME Windows)
-SET(CMAKE_SYSTEM_PROCESSOR amd64)
+SET(CMAKE_SYSTEM_PROCESSOR x86_64)
 
 # which compilers to use for C and C++
 SET(CMAKE_C_COMPILER x86_64-w64-mingw32-gcc)

libaptdec/algebra.c

@@ -52,12 +52,9 @@ linear_t linear_regression(const float *independent, const float *dependent, siz
     return (linear_t){a, b};
 }
 
+// "Sample" standard deviation
 float standard_deviation(const float *data, size_t len) {
-    float mean = 0.0f;
-    for (size_t i = 0; i < len; i++) {
-        mean += data[i];
-    }
-    mean /= (float)len;
+    float mean = meanf(data, len);
 
     float deviation_mean = 0.0f;
     for (size_t i = 0; i < len; i++) {
@@ -65,7 +62,7 @@ float standard_deviation(const float *data, size_t len) {
         deviation_mean += deviation * deviation;
     }
 
-    return sqrtf(deviation_mean / (float)len);
+    return sqrtf(deviation_mean / (float)(len-1));
 }
 
 float sumf(const float *x, size_t len) {

libaptdec/dsp.c

@@ -32,6 +32,10 @@
 #define CARRIER_FREQ 2400.0f
 #define MAX_CARRIER_OFFSET 10.0f
 
+const float sync_pattern[] = {-1, -1, -1, -1, 1, 1, -1, -1, 1, 1, -1, -1, 1,  1,  -1, -1, 1,  1,  -1, -1,
+                              1,  1,  -1, -1, 1, 1, -1, -1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, 0};
+#define SYNC_SIZE (sizeof(sync_pattern)/sizeof(sync_pattern[0]))
+
 typedef struct {
     float alpha;
     float beta;
@@ -58,6 +62,11 @@ struct aptdec_t {
     fir_t *hilbert;
 
     float low_pass[LOW_PASS_SIZE];
+    float row_buffer[APT_IMG_WIDTH + SYNC_SIZE + 2];
+
+    float interpolator_buffer[APTDEC_BUFFER_SIZE];
+    size_t interpolator_n;
+    float interpolator_offset;
 };
 
 char *aptdec_get_version(void) {
@@ -162,47 +171,38 @@ static int am_demod(aptdec_t *apt, float *out, size_t count, aptdec_callback_t c
 }
 
 static int get_pixels(aptdec_t *apt, float *out, size_t count, aptdec_callback_t callback, void *context) {
-    static float buffer[APTDEC_BUFFER_SIZE];
-    static size_t n = APTDEC_BUFFER_SIZE;
-    static float offset = 0.0;
-
     float ratio = apt->sample_rate / (4160.0f * apt->sync_frequency);
 
     for (size_t i = 0; i < count; i++) {
         // Get more samples if there are less than `LOW_PASS_SIZE` available
-        if (n + LOW_PASS_SIZE > APTDEC_BUFFER_SIZE) {
-            memcpy(buffer, &buffer[n], (APTDEC_BUFFER_SIZE-n) * sizeof(float));
+        if (apt->interpolator_n + LOW_PASS_SIZE > APTDEC_BUFFER_SIZE) {
+            memcpy(apt->interpolator_buffer, &apt->interpolator_buffer[apt->interpolator_n], (APTDEC_BUFFER_SIZE-apt->interpolator_n) * sizeof(float));
 
-            size_t read = am_demod(apt, &buffer[APTDEC_BUFFER_SIZE-n], n, callback, context);
-            if (read != n) {
+            size_t read = am_demod(apt, &apt->interpolator_buffer[APTDEC_BUFFER_SIZE-apt->interpolator_n], apt->interpolator_n, callback, context);
+            if (read != apt->interpolator_n) {
                 return i;
             }
-            n = 0;
+            apt->interpolator_n = 0;
         }
 
-        out[i] = interpolating_convolve(&buffer[n], apt->low_pass, LOW_PASS_SIZE, offset);
+        out[i] = interpolating_convolve(&apt->interpolator_buffer[apt->interpolator_n], apt->low_pass, LOW_PASS_SIZE, apt->interpolator_offset);
 
         // Do not question the sacred code
-        int shift = ceilf(ratio - offset);
-        offset = shift + offset - ratio;
-        n += shift;
+        int shift = ceilf(ratio - apt->interpolator_offset);
+        apt->interpolator_offset = shift + apt->interpolator_offset - ratio;
+        apt->interpolator_n += shift;
     }
 
     return count;
 }
 
-const float sync_pattern[] = {-1, -1, -1, -1, 1, 1, -1, -1, 1, 1, -1, -1, 1,  1,  -1, -1, 1,  1,  -1, -1,
-                              1,  1,  -1, -1, 1, 1, -1, -1, 1, 1, -1, -1, -1, -1, -1, -1, -1, -1, 0};
-#define SYNC_SIZE (sizeof(sync_pattern)/sizeof(sync_pattern[0]))
-
 // Get an entire row of pixels, aligned with sync markers
 int aptdec_getrow(aptdec_t *apt, float *row, aptdec_callback_t callback, void *context) {
-    static float pixels[APT_IMG_WIDTH + SYNC_SIZE + 2];
-
     // Wrap the circular buffer
-    memcpy(pixels, &pixels[APT_IMG_WIDTH], (SYNC_SIZE + 2) * sizeof(float));
+    memcpy(apt->row_buffer, &apt->row_buffer[APT_IMG_WIDTH], (SYNC_SIZE + 2) * sizeof(float));
+
     // Get a lines worth (APT_IMG_WIDTH) of samples
-    if (get_pixels(apt, &pixels[SYNC_SIZE + 2], APT_IMG_WIDTH, callback, context) != APT_IMG_WIDTH) {
+    if (get_pixels(apt, &apt->row_buffer[SYNC_SIZE + 2], APT_IMG_WIDTH, callback, context) != APT_IMG_WIDTH) {
         return 0;
     }
 
@@ -213,9 +213,9 @@ int aptdec_getrow(aptdec_t *apt, float *row, aptdec_callback_t callback, void *c
     size_t phase = 0;
 
     for (size_t i = 0; i < APT_IMG_WIDTH; i++) {
-        float _left   = convolve(&pixels[i + 0], sync_pattern, SYNC_SIZE);
-        float _middle = convolve(&pixels[i + 1], sync_pattern, SYNC_SIZE);
-        float _right  = convolve(&pixels[i + 2], sync_pattern, SYNC_SIZE);
+        float _left   = convolve(&apt->row_buffer[i + 0], sync_pattern, SYNC_SIZE);
+        float _middle = convolve(&apt->row_buffer[i + 1], sync_pattern, SYNC_SIZE);
+        float _right  = convolve(&apt->row_buffer[i + 2], sync_pattern, SYNC_SIZE);
         if (_middle > middle) {
             left = _left;
             middle = _middle;
@@ -226,11 +226,11 @@ int aptdec_getrow(aptdec_t *apt, float *row, aptdec_callback_t callback, void *c
 
     // Frequency
     float bias = (left / middle) - (right / middle);
-    apt->sync_frequency = 1.0f + bias / APT_IMG_WIDTH / 2.0f;
+    apt->sync_frequency = 1.0f + bias / APT_IMG_WIDTH / 4.0f;
 
     // Phase
-    memcpy(&row[APT_IMG_WIDTH], &pixels[phase], (APT_IMG_WIDTH - phase) * sizeof(float));
-    memcpy(&row[APT_IMG_WIDTH - phase], pixels, phase * sizeof(float));
+    memcpy(&row[APT_IMG_WIDTH], &apt->row_buffer[phase], (APT_IMG_WIDTH - phase) * sizeof(float));
+    memcpy(&row[APT_IMG_WIDTH - phase], apt->row_buffer, phase * sizeof(float));
 
     return 1;
 }

libaptdec/effects.c

@@ -20,6 +20,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <math.h>
+#include <stdlib.h>
 
 #include "algebra.h"
 #include "util.h"