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Add test fixture.

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This commit is contained in:
James Grogan 2022-11-29 18:00:19 +00:00
parent af6fad72eb
commit d6d4319e21
37 changed files with 421 additions and 279 deletions
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11
src/compression/Lz77Encoder.cpp
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@ -64,11 +64,9 @@ unsigned char Lz77Encoder::getSearchBufferItem(unsigned index) const
unsigned Lz77Encoder::lookAheadForMatchingChars(unsigned distance)
{
unsigned length{0};
std::cout << "In hit check at distance " << distance << " max buffer index is: " << mMaxLookAheadBufferIndex << std::endl;
for(unsigned idx=0; idx<mMaxLookAheadBufferIndex + 1; idx++)
{
int search_offset = int(distance-1) - idx;
std::cout << "Have search offet " << search_offset << std::endl;
unsigned char search_char{0};
if (search_offset < 0)
{
@ -78,10 +76,7 @@ unsigned Lz77Encoder::lookAheadForMatchingChars(unsigned distance)
{
search_char = getSearchBufferItem(static_cast<unsigned>(search_offset));
}
unsigned char lookahead_char = mLookaheadBuffer.getItem(idx);
std::cout << "Checking search char " << static_cast<int>(search_char) << " and lookup char " << static_cast<int>(lookahead_char) << std::endl;
if ((lookahead_char != search_char) || (idx == mMaxLookAheadBufferIndex))
{
if (idx + 1>= mMinLengthMatchSize)
@ -100,9 +95,7 @@ void Lz77Encoder::lookForMatches(unsigned char searchChar, unsigned& hitLength,
{
if (mSearchBuffer.getItem(mSearchBuffer.getNumItems() - 1 - idx) == searchChar)
{
std::cout << "Looking for hits " << std::endl;
auto num_hits = lookAheadForMatchingChars(idx + 1);
if (num_hits > 0 && num_hits >= hitLength)
{
hitLength = num_hits;
@ -197,14 +190,10 @@ bool Lz77Encoder::encode()
}
const auto working_byte = mLookaheadBuffer.getItem(0);
std::cout << "Working byte is " << static_cast<int>(working_byte) << std::endl;
unsigned hit_length{0};
unsigned hit_distance{0};
lookForMatches(working_byte, hit_length, hit_distance);
std::cout << "Got hit length " << hit_length << " and distance " << hit_distance << std::endl;
const Hit hit{hit_length, hit_distance, working_byte};
mHitBuffer.push_back(hit);