Index: webrtc/modules/rtp_rtcp/source/forward_error_correction_internal.cc |
diff --git a/webrtc/modules/rtp_rtcp/source/forward_error_correction_internal.cc b/webrtc/modules/rtp_rtcp/source/forward_error_correction_internal.cc |
index fae59078b1fbd80385cfbc6e143074244be57997..790e705bc4aa4e9505496e84d8e9e7cf556fdead 100644 |
--- a/webrtc/modules/rtp_rtcp/source/forward_error_correction_internal.cc |
+++ b/webrtc/modules/rtp_rtcp/source/forward_error_correction_internal.cc |
@@ -13,6 +13,8 @@ |
#include <assert.h> |
#include <string.h> |
+#include <algorithm> |
+ |
#include "webrtc/modules/rtp_rtcp/source/fec_private_tables_bursty.h" |
#include "webrtc/modules/rtp_rtcp/source/fec_private_tables_random.h" |
@@ -392,5 +394,37 @@ void GeneratePacketMasks(int num_media_packets, |
} // End of UEP modification |
} // End of GetPacketMasks |
+void InsertZeroColumns(int num_zeros, |
+ uint8_t* new_mask, |
+ int new_mask_bytes, |
+ int num_fec_packets, |
+ int new_bit_index) { |
+ for (uint16_t row = 0; row < num_fec_packets; ++row) { |
+ const int new_byte_index = row * new_mask_bytes + new_bit_index / 8; |
+ const int max_shifts = (7 - (new_bit_index % 8)); |
+ new_mask[new_byte_index] <<= std::min(num_zeros, max_shifts); |
+ } |
+} |
+ |
+void CopyColumn(uint8_t* new_mask, |
+ int new_mask_bytes, |
+ uint8_t* old_mask, |
+ int old_mask_bytes, |
+ int num_fec_packets, |
+ int new_bit_index, |
+ int old_bit_index) { |
+ // Copy column from the old mask to the beginning of the new mask and shift it |
+ // out from the old mask. |
+ for (uint16_t row = 0; row < num_fec_packets; ++row) { |
+ int new_byte_index = row * new_mask_bytes + new_bit_index / 8; |
+ int old_byte_index = row * old_mask_bytes + old_bit_index / 8; |
+ new_mask[new_byte_index] |= ((old_mask[old_byte_index] & 0x80) >> 7); |
+ if (new_bit_index % 8 != 7) { |
+ new_mask[new_byte_index] <<= 1; |
+ } |
+ old_mask[old_byte_index] <<= 1; |
+ } |
+} |
+ |
} // namespace internal |
} // namespace webrtc |