Extract key frames from fragment_buffer

[baassisnos]

System info

Operating System: Oracle Linux 9
Shaka Packager Version: 3.2.0

I would like to change the FinalizeSegment method of the segmenter.c class to save all key frames in key_frame_infos_ .

Ex:
FROM:

`

bool first_key_frame = true;
for (const std::unique_ptr<Fragmenter>& fragmenter : fragmenters_) {
// https://goo.gl/xcFus6 6. Trick play requirements
// 6.10. If using fMP4, I-frame segments must include the 'moof' header
// associated with the I-frame. It also implies that only the first key
// frame can be included.
if (!fragmenter->key_frame_infos().empty() && first_key_frame) {
  const KeyFrameInfo& key_frame_info =
      fragmenter->key_frame_infos().front();
  first_key_frame = false;
  key_frame_infos_.push_back(
      {key_frame_info.timestamp, moof_start_offset,
       fragment_buffer_->Size() - moof_start_offset + key_frame_info.size});
}
fragment_buffer_->AppendBuffer(*fragmenter->data());
  }`

TO:
`

for (const std::unique_ptr<Fragmenter>& fragmenter : fragmenters_) {
  for (const KeyFrameInfo& key_frame_info : fragmenter->key_frame_infos()) {
    if (key_frame_info.start_byte_offset > 0) {
        key_frame_infos_.push_back(
            {key_frame_info.timestamp, moof_start_offset + key_frame_info.start_byte_offset,
             fragment_buffer_->Size() - moof_start_offset + key_frame_info.size});
    } else {
        key_frame_infos_.push_back(
            {key_frame_info.timestamp, moof_start_offset,
             fragment_buffer_->Size() - moof_start_offset + key_frame_info.size});
    }
  }
  fragment_buffer_->AppendBuffer(*fragmenter->data());
}`

My intention is that in the WriteSegment method of the multi_segment_segmenter.c class I save these values ​​in a list as per the example below.
Ex:
FROM:
`

if (muxer_listener()) {
for (const KeyFrameInfo& key_frame_info : key_frame_infos()) {
  muxer_listener()->OnKeyFrame(
      key_frame_info.timestamp,
      segment_header_size + key_frame_info.start_byte_offset,
      key_frame_info.size);
}`

TO:
`

std::vector<std::pair<int, int>> iframe_list;
if (muxer_listener()) {
  int current_offset = segment_header_size;

  for (const KeyFrameInfo& key_frame_info : key_frame_infos()) {
    int key_frame_offset = current_offset + key_frame_info.start_byte_offset;

    muxer_listener()->OnKeyFrame(
        key_frame_info.timestamp,
        key_frame_offset,
        key_frame_info.size);

        iframe_list.emplace_back(key_frame_offset, key_frame_info.size);
    

  }
}	`

With this, I intend to perform a search on the final segment, extracting the key frames to a separate file.
The first key frame is extracted successfully, but I can't get the position of the second one right.
Can you see what I'm doing wrong?