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gdaladdo: reuse previous resampling method (from GTiff RESAMPLING met…
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…adata item) if not specifying -r and overview levels if not specifying them
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@rouault
rouault committed Dec 18, 2023
1 parent 1c73ebe commit d178b03
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Showing 3 changed files with 147 additions and 28 deletions.
106 changes: 81 additions & 25 deletions apps/gdaladdo.cpp
View file
Original file line number Diff line number Diff line change
Expand Up @@ -635,10 +635,9 @@ MAIN_START(nArgc, papszArgv)
if (nArgc < 1)
exit(-nArgc);

const char *pszResampling = "nearest";
std::string osResampling;
const char *pszFilename = nullptr;
int anLevels[1024] = {};
int nLevelCount = 0;
std::vector<int> anLevels;
int nResultStatus = 0;
bool bReadOnly = false;
bool bClean = false;
Expand Down Expand Up @@ -679,7 +678,7 @@ MAIN_START(nArgc, papszArgv)
else if (EQUAL(papszArgv[iArg], "-r"))
{
CHECK_HAS_ENOUGH_ADDITIONAL_ARGS(1);
pszResampling = papszArgv[++iArg];
osResampling = papszArgv[++iArg];
}
else if (EQUAL(papszArgv[iArg], "-ro"))
{
Expand Down Expand Up @@ -752,11 +751,10 @@ MAIN_START(nArgc, papszArgv)
{
pszFilename = papszArgv[iArg];
}
else if (atoi(papszArgv[iArg]) > 0 &&
static_cast<size_t>(nLevelCount) < CPL_ARRAYSIZE(anLevels))
else if (atoi(papszArgv[iArg]) > 0)
{
anLevels[nLevelCount++] = atoi(papszArgv[iArg]);
if (anLevels[nLevelCount - 1] == 1)
anLevels.push_back(atoi(papszArgv[iArg]));
if (anLevels.back() == 1)
{
printf(
"Warning: Overview with subsampling factor of 1 requested. "
Expand Down Expand Up @@ -813,24 +811,54 @@ MAIN_START(nArgc, papszArgv)
if (hDataset == nullptr)
exit(2);

if (!bClean && osResampling.empty())
{
auto poDS = GDALDataset::FromHandle(hDataset);
if (poDS->GetRasterCount() > 0)
{
auto poBand = poDS->GetRasterBand(1);
if (poBand->GetOverviewCount() > 0)
{
const char *pszResampling =
poBand->GetOverview(0)->GetMetadataItem("RESAMPLING");
if (pszResampling)
{
osResampling = pszResampling;
if (pfnProgress == GDALDummyProgress)
CPLDebug("GDAL",
"Reusing resampling method %s from existing "
"overview",
pszResampling);
else
printf("Info: reusing resampling method %s from "
"existing overview.\n",
pszResampling);
}
}
}
if (osResampling.empty())
osResampling = "nearest";
}

/* -------------------------------------------------------------------- */
/* Clean overviews. */
/* -------------------------------------------------------------------- */
if (bClean)
{
if (GDALBuildOverviews(hDataset, pszResampling, 0, nullptr, 0, nullptr,
if (GDALBuildOverviews(hDataset, "NONE", 0, nullptr, 0, nullptr,
pfnProgress, pProgressArg) != CE_None)
{
printf("Cleaning overviews failed.\n");
fprintf(stderr, "Cleaning overviews failed.\n");
nResultStatus = 200;
}
}
else if (bPartialRefreshFromSourceTimestamp)
{
if (!PartialRefreshFromSourceTimestamp(
GDALDataset::FromHandle(hDataset), pszResampling, nLevelCount,
anLevels, nBandCount, panBandList, bMinSizeSpecified, nMinSize,
pfnProgress, pProgressArg))
GDALDataset::FromHandle(hDataset), osResampling.c_str(),
static_cast<int>(anLevels.size()), anLevels.data(), nBandCount,
panBandList, bMinSizeSpecified, nMinSize, pfnProgress,
pProgressArg))
{
nResultStatus = 1;
}
Expand All @@ -839,18 +867,20 @@ MAIN_START(nArgc, papszArgv)
{
if (!PartialRefreshFromProjWin(
GDALDataset::FromHandle(hDataset), dfULX, dfULY, dfLRX, dfLRY,
pszResampling, nLevelCount, anLevels, nBandCount, panBandList,
bMinSizeSpecified, nMinSize, pfnProgress, pProgressArg))
osResampling.c_str(), static_cast<int>(anLevels.size()),
anLevels.data(), nBandCount, panBandList, bMinSizeSpecified,
nMinSize, pfnProgress, pProgressArg))
{
nResultStatus = 1;
}
}
else if (bPartialRefreshFromSourceExtent)
{
if (!PartialRefreshFromSourceExtent(
GDALDataset::FromHandle(hDataset), aosSources, pszResampling,
nLevelCount, anLevels, nBandCount, panBandList,
bMinSizeSpecified, nMinSize, pfnProgress, pProgressArg))
GDALDataset::FromHandle(hDataset), aosSources,
osResampling.c_str(), static_cast<int>(anLevels.size()),
anLevels.data(), nBandCount, panBandList, bMinSizeSpecified,
nMinSize, pfnProgress, pProgressArg))
{
nResultStatus = 1;
}
Expand All @@ -863,7 +893,32 @@ MAIN_START(nArgc, papszArgv)
/* --------------------------------------------------------------------
*/

if (nLevelCount == 0)
// If no levels are specified, reuse the potentially existing ones.
if (anLevels.empty())
{
auto poDS = GDALDataset::FromHandle(hDataset);
if (poDS->GetRasterCount() > 0)
{
auto poBand = poDS->GetRasterBand(1);
const int nExistingCount = poBand->GetOverviewCount();
if (nExistingCount > 0)
{
for (int iOvr = 0; iOvr < nExistingCount; ++iOvr)
{
auto poOverview = poBand->GetOverview(iOvr);
if (poOverview)
{
const int nOvFactor = GDALComputeOvFactor(
poOverview->GetXSize(), poBand->GetXSize(),
poOverview->GetYSize(), poBand->GetYSize());
anLevels.push_back(nOvFactor);
}
}
}
}
}

if (anLevels.empty())
{
const int nXSize = GDALGetRasterXSize(hDataset);
const int nYSize = GDALGetRasterYSize(hDataset);
Expand All @@ -872,20 +927,21 @@ MAIN_START(nArgc, papszArgv)
DIV_ROUND_UP(nYSize, nOvrFactor) > nMinSize)
{
nOvrFactor *= 2;
anLevels[nLevelCount++] = nOvrFactor;
anLevels.push_back(nOvrFactor);
}
}

// Only HFA supports selected layers
if (nBandCount > 0)
CPLSetConfigOption("USE_RRD", "YES");

if (nLevelCount > 0 &&
GDALBuildOverviews(hDataset, pszResampling, nLevelCount, anLevels,
nBandCount, panBandList, pfnProgress,
pProgressArg) != CE_None)
if (!anLevels.empty() &&
GDALBuildOverviews(hDataset, osResampling.c_str(),
static_cast<int>(anLevels.size()),
anLevels.data(), nBandCount, panBandList,
pfnProgress, pProgressArg) != CE_None)
{
printf("Overview building failed.\n");
fprintf(stderr, "Overview building failed.\n");
nResultStatus = 100;
}
}
Expand Down
51 changes: 51 additions & 0 deletions autotest/utilities/test_gdaladdo.py
View file
Original file line number Diff line number Diff line change
Expand Up @@ -324,3 +324,54 @@ def test_gdaladdo_partial_refresh_from_source_extent(gdaladdo_path, tmp_path):
ovr_data_refreshed[idx] = ovr_data_ori[idx]
assert ovr_data_refreshed == ovr_data_ori
ds = None


###############################################################################
# Test reuse of previous resampling method and overview levels


@pytest.mark.parametrize("read_only", [True, False])
def test_gdaladdo_reuse_previous_resampling_and_levels(
gdaladdo_path, tmp_path, read_only
):

tmpfilename = str(tmp_path / "test.tif")

gdal.Translate(tmpfilename, "../gcore/data/byte.tif")

out, err = gdaltest.runexternal_out_and_err(
f"{gdaladdo_path} -r average {tmpfilename}"
+ (" -ro" if read_only else "")
+ " 2 4"
)
assert "ERROR" not in err, (out, err)

ds = gdal.Open(tmpfilename)
assert ds.GetRasterBand(1).GetOverview(0).GetMetadataItem("RESAMPLING") == "AVERAGE"
assert ds.GetRasterBand(1).GetOverview(0).Checksum() == 1152
ds = None

# Change resampling method to CUBIC
out, err = gdaltest.runexternal_out_and_err(
f"{gdaladdo_path} -r cubic {tmpfilename}" + (" -ro" if read_only else "")
)
assert "ERROR" not in err, (out, err)

ds = gdal.Open(tmpfilename, gdal.GA_Update)
assert ds.GetRasterBand(1).GetOverview(0).GetMetadataItem("RESAMPLING") == "CUBIC"
assert ds.GetRasterBand(1).GetOverview(0).Checksum() == 1059
# Zeroize overview
ds.GetRasterBand(1).GetOverview(0).Fill(0)
ds = None

# Invoke gdaladdo without arguments and check overviews are regenerated
# using CUBIC
out, err = gdaltest.runexternal_out_and_err(
f"{gdaladdo_path} {tmpfilename}" + (" -ro" if read_only else "")
)
assert "ERROR" not in err, (out, err)

ds = gdal.Open(tmpfilename)
assert ds.GetRasterBand(1).GetOverview(0).GetMetadataItem("RESAMPLING") == "CUBIC"
assert ds.GetRasterBand(1).GetOverview(0).Checksum() == 1059
ds = None
18 changes: 15 additions & 3 deletions doc/source/programs/gdaladdo.rst
View file
Original file line number Diff line number Diff line change
Expand Up @@ -35,9 +35,16 @@ most supported file formats with one of several downsampling algorithms.

.. option:: -r {nearest|average|rms|gauss|cubic|cubicspline|lanczos|average_magphase|mode}

Select a resampling algorithm.
Select a resampling algorithm. The default is ``nearest``, which is generally not
appropriate if sub-pixel accuracy is desired.

``nearest`` applies a nearest neighbour (simple sampling) resampler (default)
Starting with GDAL 3.9, when refreshing existing TIFF overviews, the previously
used method, as noted in the RESAMPLING metadata item of the overview, will
be used if :option:`-r` is not specified.

The available methods are:

``nearest`` applies a nearest neighbour (simple sampling) resampler.

``average`` computes the average of all non-NODATA contributing pixels. Starting with GDAL 3.1, this is a weighted average taking into account properly the weight of source pixels not contributing fully to the target pixel.

Expand Down Expand Up @@ -131,10 +138,15 @@ most supported file formats with one of several downsampling algorithms.

.. versionadded:: 2.3

levels are no longer required to build overviews.
Levels are no longer required to build overviews.
In which case, appropriate overview power-of-two factors will be selected
until the smallest overview is smaller than the value of the -minsize switch.

Starting with GDAL 3.9, if there are already existing overviews, the
corresponding levels will be used to refresh them if no explicit levels
are specified.


gdaladdo will honour properly NODATA_VALUES tuples (special dataset metadata) so
that only a given RGB triplet (in case of a RGB image) will be considered as the
nodata value and not each value of the triplet independently per band.
Expand Down

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