c++ - Decoding by libjpeg -> Encoding by x264, strange artefacts on frames -

i have collection of jpeg, must decoded lib jpeg, , after it, encoded x264 (after encoded packets streamed via rtmp). code used decoding:

struct my_error_mgr  {        struct jpeg_error_mgr pub;     jmp_buf setjmp_buffer; }; typedef my_error_mgr *my_error_ptr;  methoddef(void) my_error_exit (j_common_ptr cinfo) {     my_error_ptr myerr = (my_error_ptr) cinfo->err;     (*cinfo->err->output_message) (cinfo);     longjmp(myerr->setjmp_buffer, 1);    }  void init_source(j_decompress_ptr ptr) {     q_unused(ptr) }  boolean fill_input_buffer(j_decompress_ptr ptr)  {      q_unused(ptr)     return true; }  void term_source(j_decompress_ptr ptr) {     q_unused(ptr) }  void skip_input_data(j_decompress_ptr ptr, long num_bytes) {     if(num_bytes>0)      {         ptr->src->next_input_byte+=(size_t)num_bytes;         ptr->src->bytes_in_buffer-=(size_t)num_bytes;        } }  etherdecoder::etherdecoder(qobject *parent): qobject(parent) { }  void etherdecoder::datablockready(qbytearray data) {     jpeg_decompress_struct decompressinfo;     jpeg_create_decompress(&decompressinfo);     my_error_mgr err;     decompressinfo.do_fancy_upsampling = false;     decompressinfo.src = (jpeg_source_mgr *) (*decompressinfo.mem->alloc_small)       ((j_common_ptr) &decompressinfo, jpool_permanent, sizeof(jpeg_source_mgr));     decompressinfo.err = jpeg_std_error(&err.pub);     err.pub.error_exit = my_error_exit;     if (setjmp(err.setjmp_buffer))       {         jpeg_destroy_decompress(&decompressinfo);         return;      }     decompressinfo.src->init_source = init_source;     decompressinfo.src->resync_to_restart = jpeg_resync_to_restart;     decompressinfo.src->fill_input_buffer = fill_input_buffer;     decompressinfo.src->skip_input_data = skip_input_data;     decompressinfo.src->term_source = term_source;     decompressinfo.src->next_input_byte = reinterpret_cast<const joctet*>(data.data());     decompressinfo.src->bytes_in_buffer = data.size();     jpeg_read_header(&decompressinfo, true);     jpeg_start_decompress(&decompressinfo);     int size = 0;     int n_samples = 0;     char *samples = new char[5242880];     char *reserv = samples;     while (decompressinfo.output_scanline < decompressinfo.output_height)        {         n_samples = jpeg_read_scanlines(&decompressinfo, (jsamparray) &samples, 1);         samples += n_samples * decompressinfo.image_width * decompressinfo.num_components;         size += n_samples * decompressinfo.image_width * decompressinfo.num_components;      }     jpeg_finish_decompress(&decompressinfo);     qbytearray output(reserv, size);     emit frameready(output, decompressinfo.output_width, decompressinfo.output_height);     jpeg_destroy_decompress(&decompressinfo);     delete[] reserv; } 

when emit frameready signal, send data encoder, method, init encedor looks like:

bool etherencoder::initencoder(unsigned int width, unsigned int height) {     x264_param_t param;     x264_param_default_preset(&param, "veryfast", "zerolatency");     param.i_width=width;     param.i_height=height;     param.i_frame_total=0;     param.i_csp=x264_csp_i420;     param.i_timebase_num=1;     param.i_timebase_den=96000;     param.b_annexb=true;     param.b_repeat_headers=false;     x264_param_apply_fastfirstpass(&param);     x264_param_apply_profile(&param, "baseline");     _context=x264_encoder_open(&param);     if(!_context)         return false;     int nal_count;     x264_nal_t *nals;     if(x264_encoder_headers(_context, &nals, &nal_count)<0)      {         x264_encoder_close(_context);         _context=0;         return false;        }     _extradata=qbytearray();     _width=width;     _height=height;     if(nal_count>0)      {         _extradata=qbytearray(             (const char *)nals[0].p_payload,             nals[nal_count-1].p_payload+nals[nal_count-1].i_payload-nals[0].p_payload);      }     return true; } 

and encoding method:

void etherencoder::onframeready(qbytearray data, int width, int height) {     while(data.size()>0)         {         if(!_context && initencoder(width, height))         {             _timestampdelta=realtimestamp();         }         if(_context)         {             x264_picture_t pic;             x264_picture_init(&pic);             pic.i_type=x264_type_auto;             pic.i_pts=_timestampdelta*96000;             pic.img.i_csp=x264_csp_i420;             pic.img.i_plane=3;             int planesize = width*height;             uint8_t *p = (uint8_t*)data.data();             pic.img.plane[0]=p;             p+=planesize;             pic.img.plane[1]=p;             p+=planesize/4;             pic.img.plane[2]=p;             pic.img.i_stride[0]=width;             pic.img.i_stride[1]=width/2;             pic.img.i_stride[2]=width/2;             if(_forcekeyframe)             {                 pic.i_type=x264_type_i;                 _forcekeyframe=false;             }             int nal_count;             x264_nal_t *nals;             int rc=x264_encoder_encode(_context, &nals, &nal_count, &pic, &pic);             if(rc>0)             {                 _mutex.lock();                 _packets.push_back(                     packet(                         qbytearray(                             (const char *)nals[0].p_payload,         nals[nal_count-    1].p_payload+nals[nal_count-1].i_payload-nals[0].p_payload),                         _timestampdelta/96.0,                         _timestampdelta/96.0,                         pic.b_keyframe));                 _timestampdelta+=40;                 data.clear();                 _mutex.unlock();                 emit onpacketready();             }         }        } } 

decoding , encoding proceeds without errors, @ end valid video stream, but, seems in 1 of steps set invalid data decoder/encoder. 1/4 part of image (top-left, understood) , has invalid color , come color stripes. maybe set invalid strides , planes when encode frame, or maybe setting data libjpeg decoder incorrect.. please ask questions code, i'll try make explanations you. explodes brain.. thank you.