LIBDE265_API de265_error de265_decode(de265_decoder_context* de265ctx, int* more)
{
decoder_context* ctx = (decoder_context*)de265ctx;
// if the stream has ended, and no more NALs are to be decoded, flush all pictures
if (ctx->NAL_queue_len == 0 && ctx->end_of_stream) {
if (more) { *more=0; } // 0 if no more pictures in queue
push_current_picture_to_output_queue(ctx);
while (ctx->reorder_output_queue_length>0) {
flush_next_picture_from_reorder_buffer(ctx);
if (more) { *more=1; }
}
return DE265_OK;
}
// if NAL-queue is empty, we need more data
// -> input stalled
if (ctx->NAL_queue_len == 0) {
if (more) { *more=1; }
return DE265_ERROR_WAITING_FOR_INPUT_DATA;
}
// when there are no free image buffers in the DPB, pause decoding
// -> output stalled
if (!has_free_dpb_picture(ctx, false)) {
if (more) *more = 1;
return DE265_ERROR_IMAGE_BUFFER_FULL;
}
// decode one NAL from the queue
NAL_unit* nal = pop_from_NAL_queue(ctx);
assert(nal);
de265_error err = de265_decode_NAL(de265ctx, nal);
free_NAL_unit(ctx,nal);
if (more) {
// decoding error is assumed to be unrecoverable
*more = (err==DE265_OK);
}
return err;
}
static de265_error process_data(decoder_context* ctx, const uint8_t* data, int len,
int* out_nBytesProcessed)
{
*out_nBytesProcessed=0;
/*
printf("len=%d\n",len);
for (int i=0;i<16;i++) {
printf("%02x ",data[i]);
}
printf("\n");
*/
// Resize output buffer so that complete input would fit.
// We add 3, because in the worst case 3 extra bytes are created for an input byte.
rbsp_buffer_resize(&ctx->nal_data, ctx->nal_data.size + len + 3);
unsigned char* out = ctx->nal_data.data + ctx->nal_data.size;
for (int i=0;i<len;i++) {
(*out_nBytesProcessed)++;
/*
printf("state=%d input=%02x (%p) (output size: %d)\n",ctx->input_push_state, *data, data,
out - ctx->nal_data.data);
*/
switch (ctx->input_push_state) {
case 0:
case 1:
if (*data == 0) { ctx->input_push_state++; }
else { return DE265_ERROR_NO_STARTCODE; }
break;
case 2:
if (*data == 1) { ctx->input_push_state=3; ctx->num_skipped_bytes=0; }
else if (*data == 0) { } // *out++ = 0; }
else { return DE265_ERROR_NO_STARTCODE; }
break;
case 3:
/*
*out++ = 0;
*out++ = 0;
*out++ = 1;
*/
*out++ = *data;
ctx->input_push_state = 4;
break;
case 4:
*out++ = *data;
ctx->input_push_state = 5;
break;
case 5:
if (*data==0) { ctx->input_push_state=6; }
else { *out++ = *data; }
break;
case 6:
if (*data==0) { ctx->input_push_state=7; }
else {
*out++ = 0;
*out++ = *data;
ctx->input_push_state=5;
}
break;
case 7:
if (*data==0) { *out++ = 0; }
else if (*data==3) {
*out++ = 0; *out++ = 0; ctx->input_push_state=5;
// remember which byte we removed
int* skipped = (int *)malloc((ctx->num_skipped_bytes+1) * sizeof(int));
if (ctx->num_skipped_bytes>0) {
memcpy(skipped, ctx->skipped_bytes, ctx->num_skipped_bytes * sizeof(int));
}
if (ctx->skipped_bytes) {
free(ctx->skipped_bytes);
}
skipped[ctx->num_skipped_bytes] = (out - ctx->nal_data.data) + ctx->num_skipped_bytes;
ctx->skipped_bytes = skipped;
ctx->num_skipped_bytes++;
}
else if (*data==1) {
// decode this NAL
ctx->nal_data.size = out - ctx->nal_data.data;
de265_error err = de265_decode_NAL((de265_decoder_context*)ctx, &ctx->nal_data);
// clear buffer for next NAL
ctx->nal_data.size = 0;
out = ctx->nal_data.data;
ctx->input_push_state=3;
ctx->num_skipped_bytes=0;
if (err != DE265_OK) {
data++;
return err;
}
// when there are no free image buffers in the DPB, pause decoding
if (!has_free_dpb_picture(ctx)) {
data++;
return err;
}
}
else {
*out++ = 0;
*out++ = 0;
*out++ = *data;
ctx->input_push_state=5;
}
break;
}
data++;
/*
for (int i=0;i<out - ctx->nal_data.data;i++) {
printf("%02x ",ctx->nal_data.data[i]);
}
printf("\n");
*/
}
if (*out_nBytesProcessed == len && ctx->end_of_stream &&
ctx->input_push_state != 8) {
if (ctx->input_push_state<5) { return DE265_ERROR_EOF; }
else if (ctx->input_push_state==6) { *out++ = 0; }
else if (ctx->input_push_state==7) { *out++ = 0; *out++ = 0; }
ctx->input_push_state=8; // end of stream, stop all processing
// decode data
ctx->nal_data.size = out - ctx->nal_data.data;
de265_error err = de265_decode_NAL((de265_decoder_context*)ctx, &ctx->nal_data);
if (err != DE265_OK) {
return err;
}
push_current_picture_to_output_queue(ctx);
// clear buffer
ctx->nal_data.size = 0;
out = ctx->nal_data.data;
return DE265_OK;
}
ctx->nal_data.size = out - ctx->nal_data.data;
return DE265_OK;
}
