add links to HM, VTM, and ECM.

README.md

@@ -15,14 +15,7 @@ Please note that different methods may use different configurations to test diff
 
 So, it does not make sense to compare the numbers in different methods directly, unless making sure they are using same test conditions.
 
-Please find more details on the [test_conditions](./test_conditions.md).
-
-# Command line to generate VTM results
-
-Get VTM from https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM and build the project.
-```bash
-EncoderApp -c encoder_lowdelay_vtm.cfg --InputFile={input file name} --BitstreamFile={bitstream file name} --DecodingRefreshType=2 --InputBitDepth=8 --OutputBitDepth=8 --OutputBitDepthC=8 --InputChromaFormat=444 --FrameRate={frame rate} --FramesToBeEncoded={frame number} --SourceWidth={width} --SourceHeight={height} --IntraPeriod=32 --QP={qp} --Level=6.2
-```
+Please find more details on the [test conditions](./test_conditions.md).
 
 # Acknowledgement
 The implementation is based on [CompressAI](https://github.com/InterDigitalInc/CompressAI) and [PyTorchVideoCompression](https://github.com/ZhihaoHu/PyTorchVideoCompression).

test_conditions.md

@@ -35,7 +35,7 @@ When comparing with traditional codecs, it is highly suggested to use the settin
 * Use 10-bit as internal bit-depth. (6% gap over 8-bit)
 * Use YUV420 when comparing for YUV420 source content and use YUV444 when comparing RGB content. (22% gap when using different color spaces)
 
-We suggest using the official reference software (HM, VTM, and ECM) to generate tradition codec anchors. For low delay encoding, the suggested command lines are as follows. We suggest using HM-16.25, VTM-17.0, and ECM-5.0 as traditional codec reference. Using a more recent version is also preferred.
+We suggest using the official reference software ([HM](https://vcgit.hhi.fraunhofer.de/jvet/HM), [VTM](https://vcgit.hhi.fraunhofer.de/jvet/VVCSoftware_VTM), and [ECM](https://jvet-experts.org/doc_end_user/documents/27_Teleconference/wg11/JVET-AA0006-v1.zip)) to generate tradition codec anchors. For low delay encoding, the suggested command lines are as follows. We suggest using HM-16.25, VTM-17.0, and ECM-5.0 as traditional codec reference. Using a more recent version is also preferred.
 
 ### Encoding for RGB content