feature (thumb): support for webp

server/plugin/plg_image_c/image_webp.c

@@ -0,0 +1,106 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <webp/decode.h>
+#include <webp/encode.h>
+#include "utils.h"
+
+#define WEBP_QUALITY 75
+#define INITIAL_BUFFER_SIZE 1024*64 // 128kB
+#define MAX_BUFFER_SIZE 1024*1024*2 // 2MB
+
+int webp_to_webp(int inputDesc, int outputDesc, int targetSize) {
+#ifdef HAS_DEBUG
+  clock_t t;
+  t = clock();
+#endif
+  if (targetSize < 0) {
+    targetSize = -targetSize;
+  }
+  int status = 0;
+  FILE* input = fdopen(inputDesc, "rb");
+  FILE* output = fdopen(outputDesc, "wb");
+  if (!input || !output) {
+    ERROR("setup");
+    return 1;
+  }
+
+  // STEP1: setup everything
+  size_t data_size = 0;
+  size_t buffer_size = INITIAL_BUFFER_SIZE;
+  uint8_t* data = (uint8_t*)malloc(buffer_size);
+  if (!data) {
+    ERROR("malloc");
+    return 1;
+  }
+  size_t bytes_read;
+  while ((bytes_read = fread(data + data_size, 1, buffer_size - data_size, input)) > 0) {
+    data_size += bytes_read;
+    if (buffer_size - data_size == 0) {
+      DEBUG("realloc");
+      if (buffer_size >= MAX_BUFFER_SIZE) {
+        free(data);
+        ERROR("abort");
+        return 1;
+      }
+      buffer_size *= 2;
+      if (buffer_size > MAX_BUFFER_SIZE) buffer_size = MAX_BUFFER_SIZE;
+      uint8_t* new_data = (uint8_t*)realloc(data, buffer_size);
+      if (!new_data) {
+        free(data);
+        ERROR("realloc");
+        return 1;
+      }
+      data = new_data;
+    }
+  }
+
+  // STEP2: decode
+  int width, height, scale_factor;
+  if (!WebPGetInfo(data, data_size, &width, &height)) {
+    free(data);
+    ERROR("init");
+    return 1;
+  }
+  DEBUG("init");
+  WebPDecoderConfig config;
+  if (!WebPInitDecoderConfig(&config)) {
+    free(data);
+    ERROR("config");
+    return 1;
+  }
+  scale_factor = (height > targetSize) ? height / targetSize : 1;
+  config.options.use_scaling = 1;
+  config.options.scaled_width = width / scale_factor;
+  config.options.scaled_height = height / scale_factor;
+  config.output.colorspace = MODE_rgbA;
+  DEBUG("config");
+  if (WebPDecode(data, data_size, &config) != VP8_STATUS_OK) {
+    WebPFreeDecBuffer(&config.output);
+    free(data);
+    ERROR("decode");
+    return 1;
+  }
+  free(data);
+  DEBUG("decode");
+
+  // STEP3: encode
+  size_t output_size = 0;
+  uint8_t* output_data = NULL;
+  output_size = WebPEncodeRGBA(
+      config.output.u.RGBA.rgba, config.options.scaled_width,
+      config.options.scaled_height, config.output.u.RGBA.stride,
+      WEBP_QUALITY, &output_data
+  );
+  if (output_data == NULL) {
+    WebPFreeDecBuffer(&config.output);
+    ERROR("encode");
+    return 1;
+  }
+  DEBUG("encode");
+  fwrite(output_data, output_size, 1, output);
+  fflush(output);
+  WebPFree(output_data);
+  WebPFreeDecBuffer(&config.output);
+  DEBUG("done");
+  return status;
+}

server/plugin/plg_image_c/image_webp.go

@@ -0,0 +1,10 @@
+package plg_image_c
+
+// #include "image_webp.h"
+// #cgo LDFLAGS: -l:libwebp.a
+import "C"
+
+func webp(input uintptr, output uintptr, size int) {
+	C.webp_to_webp(C.int(input), C.int(output), C.int(size))
+	return
+}

server/plugin/plg_image_c/image_webp.h

@@ -0,0 +1 @@
+int webp_to_webp(int inputDesc, int outputDesc, int targetSize);

server/plugin/plg_image_c/index.go

@@ -30,6 +30,8 @@ func init() {
 	Hooks.Register.Thumbnailer("image/png", &transcoder{runner(png), "image/webp", -200})
 	Hooks.Register.Thumbnailer("image/gif", &transcoder{runner(gif), "image/webp", -300})
 	Hooks.Register.Thumbnailer("image/heic", &transcoder{runner(heif), "image/jpeg", -200})
+	Hooks.Register.Thumbnailer("image/webp", &transcoder{runner(webp), "image/webp", -200})
+
 	rawMimeType := []string{
 		"image/x-canon-cr2", "image/x-tif", "image/x-canon-cr2", "image/x-canon-crw",
 		"image/x-nikon-nef", "image/x-nikon-nrw", "image/x-sony-arw", "image/x-sony-sr2",