goheif's Introduction

GoHeif - A go gettable decoder/converter for HEIC based on libde265

Intel and ARM supported

Install

go get github.com/tagatac/goheif

Code Sample

func main() {
	flag.Parse()
	...
  
	fin, fout := flag.Arg(0), flag.Arg(1)
	fi, err := os.Open(fin)
	if err != nil {
		log.Fatal(err)
	}
	defer fi.Close()

	exif, err := goheif.ExtractExif(fi)
	if err != nil {
		log.Printf("Warning: no EXIF from %s: %v\n", fin, err)
	}

	img, err := goheif.Decode(fi)
	if err != nil {
		log.Fatalf("Failed to parse %s: %v\n", fin, err)
	}

	fo, err := os.OpenFile(fout, os.O_RDWR|os.O_CREATE, 0644)
	if err != nil {
		log.Fatalf("Failed to create output file %s: %v\n", fout, err)
	}
	defer fo.Close()

	w, _ := newWriterExif(fo, exif)
	err = jpeg.Encode(w, img, nil)
	if err != nil {
		log.Fatalf("Failed to encode %s: %v\n", fout, err)
	}

	log.Printf("Convert %s to %s successfully\n", fin, fout)
}

What is done

Changes make to @bradfitz's (https://github.com/bradfitz) golang heif parser
- Some minor bugfixes
- A few new box parsers, noteably 'iref' and 'hvcC'
Include libde265's source code (SSE by default enabled) and a simple golang binding
A Utility heic2jpg to illustrate the usage.

License

heif and libde265 are in their own licenses
goheif.go, libde265 golang binding and the heic2jpg utility are in MIT license

Credits

heif parser by @bradfitz (https://github.com/go4org/go4/tree/master/media/heif)
libde265 (https://github.com/strukturag/libde265)
implementation learnt from libheif (https://github.com/strukturag/libheif)

TODO

Upstream the changes to heif?

goheif's People

Contributors

Watchers

goheif's Issues

Add tests for the heic2jpg.Converter interface

Upstream colorspace and chroma type getters to libheif

Use submodules for copied code

I actually spent some time on this, and the rabbit hole goes deeper than you would expect. Here's what I've gleaned:

The libde265 repo uses CMake to generate intermediate files based on the target platform.
The goheif repo has made enough of these changes directly to the source to allow the build to pass.
A SWIG wrapper may be the way to go for automated integration of a CMake-based C++ library into a Go library, but SWIG usage is not simple.

Here are the differences between https://github.com/strukturag/libde265/tree/v1.0.8/libde265 and https://github.com/adrium/goheif/tree/master/libde265/libde265:

diff --git a/libde265/cabac.cc b/libde265/cabac.cc
index 102bc57e..6ea5b5ba 100644
--- a/libde265/cabac.cc
+++ b/libde265/cabac.cc
@@ -416,8 +416,6 @@ int  decode_CABAC_TR_bypass(CABAC_decoder* decoder, int cRiceParam, int cTRMax)
 }


-#define MAX_PREFIX 32
-
 int  decode_CABAC_EGk_bypass(CABAC_decoder* decoder, int k)
 {
   int base=0;
@@ -433,7 +431,7 @@ int  decode_CABAC_EGk_bypass(CABAC_decoder* decoder, int k)
         n++;
       }

-      if (n == k+MAX_PREFIX) {
+      if (n == k+32) {
         return 0; // TODO: error
       }
     }
diff --git a/libde265/fallback-motion.cc b/libde265/fallback-motion.cc
index 1ac41da4..3a386e23 100644
--- a/libde265/fallback-motion.cc
+++ b/libde265/fallback-motion.cc
@@ -475,8 +475,8 @@ void put_qpel_0_0_fallback_16(int16_t *out, ptrdiff_t out_stride,



-static int extra_before[4] = { 0,3,3,2 };
-static int extra_after [4] = { 0,3,4,4 };
+static int fallback_extra_before[4] = { 0,3,3,2 };
+static int fallback_extra_after [4] = { 0,3,4,4 };

 template <class pixel_t>
 void put_qpel_fallback(int16_t *out, ptrdiff_t out_stride,
@@ -484,10 +484,10 @@ void put_qpel_fallback(int16_t *out, ptrdiff_t out_stride,
                        int nPbW, int nPbH, int16_t* mcbuffer,
                        int xFracL, int yFracL, int bit_depth)
 {
-  int extra_left   = extra_before[xFracL];
-  //int extra_right  = extra_after [xFracL];
-  int extra_top    = extra_before[yFracL];
-  int extra_bottom = extra_after [yFracL];
+  int extra_left   = fallback_extra_before[xFracL];
+  //int extra_right  = fallback_extra_after [xFracL];
+  int extra_top    = fallback_extra_before[yFracL];
+  int extra_bottom = fallback_extra_after [yFracL];

   //int nPbW_extra = extra_left + nPbW + extra_right;
   int nPbH_extra = extra_top  + nPbH + extra_bottom;
diff --git a/libde265/slice.cc b/libde265/slice.cc
index e85ecc61..5e8a6f8e 100644
--- a/libde265/slice.cc
+++ b/libde265/slice.cc
@@ -2444,8 +2444,6 @@ static int decode_coeff_abs_level_greater2(thread_context* tctx,
 }


-#define MAX_PREFIX 64
-
 static int decode_coeff_abs_level_remaining(thread_context* tctx,
                                             int cRiceParam)
 {
@@ -2457,7 +2455,7 @@ static int decode_coeff_abs_level_remaining(thread_context* tctx,
     prefix++;
     codeword = decode_CABAC_bypass(&tctx->cabac_decoder);

-    if (prefix>MAX_PREFIX) {
+    if (prefix>64) {
       return 0; // TODO: error
     }
   }

Originally posted by @tagatac in jdeng#21 (comment)