/*
* @brief get next apng frame
*/
void apng_ani::next_frame()
{
_reading = false;
// setup new frame (if frame doesn't already exist)
// always do if not caching
// don't do if caching & already have frame
if (_cache == false || (_frames.size() <= current_frame)) {
if (current_frame > 0) {
if (_dispose_op == 1) {
// clear previous frame region of output buffer to fully transparent black
for (uint row = 0; row < _frameh; ++row) {
memset(&frame.data.at((_y_offset+row) * _row_len + _x_offset * 4), 0, _framew * 4);
}
}
else if (_dispose_op == 2) {
// revert previous frames region of output buffer to previous contents
for (uint row = 0; row < _frameh; ++row) {
uint pos = (_y_offset+row) * _row_len + _x_offset * 4;
memcpy(&frame.data.at(pos), &_frame_next.data.at(pos), _framew * 4);
}
}
// default is to do nothing with output buffer
}
while (cftell(_cfp) < _frame_offsets.at(current_frame+1)) {
_process_chunk();
}
nprintf(("apng", "apng next_frame; new (%03i/%03u/%03i) (%u) (%u) %03u|%03u %03u|%03u (%02u) (%04f)\n",
current_frame, static_cast<uint>(_frames.size()), nframes, _dispose_op, _blend_op,
_framew, _x_offset, _frameh, _y_offset,
static_cast<uint>(_frame_offsets.size()), frame.delay));
if (_got_IDAT && _processing_finish()) {
_apng_failed("couldn't finish fdat apng frame");
}
if (_dispose_op == 2) {
// revert to previous; so save the current frame region for later
for (uint row = 0; row < _frameh; ++row) {
uint pos = (_y_offset+row) * _row_len + _x_offset * 4;
memcpy(&_frame_next.data.at(pos), &frame.data.at(pos), _framew * 4);
}
}
_compose_frame();
if (_cache == true) _frames.push_back(frame);
}
else {
if (current_frame < nframes) {
nprintf(("apng", "apng next_frame; used old (%03i/%03u)\n", current_frame, static_cast<uint>(_frames.size())));
frame = _frames.at(current_frame);
}
}
++current_frame;
}
void AudioEffectDelayInstance::process(const AudioFrame *p_src_frames,AudioFrame *p_dst_frames,int p_frame_count) {
int todo = p_frame_count;
while(todo) {
int to_mix = MIN(todo,256); //can't mix too much
_process_chunk(p_src_frames,p_dst_frames,to_mix);
p_src_frames+=to_mix;
p_dst_frames+=to_mix;
todo-=to_mix;
}
}
/*
* @brief Get info about the apng
* @note Also validates the apng & sets it up to have frames read
*
* @retval PNG_ERROR_NONE (0), otherwise will raise exception
*/
int apng_ani::load_header()
{
char filename[MAX_FILENAME_LEN];
strcpy_s(filename, _filename.c_str());
char *p = strchr( filename, '.' );
if ( p != nullptr ) *p = 0;
strcat_s( filename, ".png" );
_cfp = cfopen( filename , "rb" );
if ( _cfp == nullptr) {
_apng_failed("couldn't open filename");
}
_reading = true;
ubyte sig[8];
if (cfread(sig, 8, 1, _cfp) != 1) {
_apng_failed("cfread of png signature failed");
}
if (png_sig_cmp(sig, 0, 8) != 0) {
_apng_failed("file has invalid png signature");
}
// setup chunk sizes before use
_chunk_IHDR.data.resize(25); // fixed IHDR chunk size
_chunk.data.resize(25); // match the other sizes, maybe waste up to 13 bytes (ooooh)
_id = _read_chunk(_chunk_IHDR);
if (_id != id_IHDR || _chunk_IHDR.size != 25) {
_apng_failed("failed to read IHDR chunk");
}
w = png_get_uint_32(&_chunk_IHDR.data[8]);
h = png_get_uint_32(&_chunk_IHDR.data[12]);
_row_len = w * 4;
// setup frames & keep bm_create happy
_image_size = _row_len * h;
frame.data.reserve(_image_size); // alloc only once
frame.data.assign(_image_size, 0); // all transparent black per spec
frame.rows.resize(h);
_frame_raw.data.resize(_image_size);
_frame_raw.rows.resize(h);
_frame_next.data.resize(_image_size);
_frame_next.rows.resize(h);
for (uint i = 0; i < h; ++i) {
// everything is correctly sized above; avoid .at() error checks
frame.rows[i] = &frame.data[i * _row_len];
_frame_raw.rows[i] = &_frame_raw.data[i * _row_len];
_frame_next.rows[i] = &_frame_next.data[i * _row_len];
}
// read all data
while (!cfeof(_cfp)) {
_process_chunk();
}
// should be at EOF; attach to _frame_offsets to make next_frame code simpler
Assertion(cfeof(_cfp) != 0, "apng not at EOF, get a coder!");
_frame_offsets.push_back(cftell(_cfp));
// sanity checks
if (anim_time <= 0.0f) {
_apng_failed("animation duration <= 0.0f, bad data?");
}
if (nframes < 1) {
_apng_failed("animation didn't have any frames, is this a static png?");
}
// back to start, including reset of _cfp so it can be used for the 1st frame
_reading = false;
if (cfseek(_cfp, _frame_offsets.at(0), CF_SEEK_SET) != 0) {
_apng_failed("couldn't seek to 1st fcTL offset");
}
return PNG_ERROR_NONE;
}