From 4e0564307f3d700c4a11dad7e84997ca988715ff Mon Sep 17 00:00:00 2001
From: Cacsjep <c.acs@commend.at>
Date: Fri, 29 Mar 2024 07:38:32 +0100
Subject: [PATCH] add SetExtraData

---
 codec_parameters.go | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/codec_parameters.go b/codec_parameters.go
index f77b20a..536539a 100644
--- a/codec_parameters.go
+++ b/codec_parameters.go
@@ -3,6 +3,10 @@ package astiav
 //#cgo pkg-config: libavcodec
 //#include <libavcodec/avcodec.h>
 import "C"
+import (
+	"fmt"
+	"unsafe"
+)
 
 // https://github.com/FFmpeg/FFmpeg/blob/n5.0/libavcodec/codec_par.h#L52
 type CodecParameters struct {
@@ -141,6 +145,27 @@ func (cp *CodecParameters) SetSampleAspectRatio(r Rational) {
 	cp.c.sample_aspect_ratio = r.c
 }
 
+func (cp *CodecParameters) SetExtraData(extraData []byte) error {
+	if len(extraData) == 0 {
+		return nil
+	}
+
+	if cp.c.extradata != nil {
+		C.av_freep(unsafe.Pointer(&cp.c.extradata))
+		cp.c.extradata_size = 0
+	}
+
+	extradataSize := len(extraData)
+	cp.c.extradata = (*C.uint8_t)(C.av_mallocz(C.size_t(extradataSize + C.AV_INPUT_BUFFER_PADDING_SIZE)))
+	if cp.c.extradata == nil {
+		return fmt.Errorf("failed to allocate extradata")
+	}
+
+	C.memcpy(unsafe.Pointer(cp.c.extradata), unsafe.Pointer(&extraData[0]), C.size_t(extradataSize))
+	cp.c.extradata_size = C.int(extradataSize)
+	return nil
+}
+
 func (cp *CodecParameters) SampleFormat() SampleFormat {
 	return SampleFormat(cp.c.format)
 }