From its datasheet, here are the specs of Freescale H264 encoder:
• 1/4-pel accuracy motion estimation with programmable search range up to [+/-128, +/-64]
• Search range is reconfigurable by SW
• 16x16, 16x8, 8x16 and 8x8 block sizes
• Configurable block sizes
• Only one reference frame for motion estimation
• Luma I4x4 Mode : 9 modes
• Luma I16x16 Mode : 3 modes (Vertical, Horizon, DC)
• Chroma Mode : 3 modes (Vertical, Horizon, DC)
• Minimum encoding image size is 96 pixels in horizontal and 16 pixels in vertical
• The encoder supports the following error resilience tools: video packet (fixed number of bits, and fixed number of macroblocks), CIR (Cyclic Intra Refresh), and multi-slice structure.
• The encoder rate control is configurable for low-delay and long-delay, and it is configurable from macroblock-level rate control to frame-level rate control.
Currently I am using it as Constrained Baseline encoder in my applications.