IP Camera Manufacturer Compression Comparison
Despite the use of standards-based video compression (H.264/H.265), our tests show that default image quality settings for different manufacturers vary widely, with no standards for terminology or scale used. This can result in two cameras with the same resolution produced by two different manufacturers producing widely different out-of-the-box results.
To help clear this confusion, IPVM has analyzed cameras from 10 manufacturers and answered these key questions:
- What is the real H.264 and/or H265 quantization level for each camera manufacturer's default settings? How do they vary? Who defaults the lowest and highest?
- To normalize the H.264/H.265 quantization levels so that each manufacturer had the same compression, what camera settings should be used?
- What is the impact of bandwidth as H.264/H.265 quantization/compression levels are varied for different manufacturers?
- What impact do smart codecs have on these settings?
Here is what we found for default settings from these manufacturers, showing manufacturer with the highest default compression (Bosch), 50% higher than the manufacturer with the lowest default compression (Arecont):
If you really care about image quality and optimizing bandwidth / storage use, this is a critical report.
Key Findings
Here are the key findings from this test:
- Average default quantization: Based on our tests, average default quantization is ~25, with cameras varying widely, from ~20 to 30.
- H.265 quantization levels similar to H.264: Testing multiple manufacturers' H.265 cameras, we found that quantization was approximately similar when using H.265 and H.264, though bandwidth was notably lower using H.265.
- Strong bandwidth impact: As a rule of thumb, going from highly compressed Q35 to more average Q28 resulted in a 3x-5x bandwidth increase, varying by manufacturer. Q34 to Q22 was a roughly 5x-10x increase.
- No correlation between manufacturers: Of the 11 manufacturers tested, none used the same naming conventions and scale, nor did similar terms (such as "medium") result in similar quantization levels.
Video Compression Overview
Understanding compression, and how manufacturers try to hide actual quantization level settings, is very important. While resolution gets the attention, compression is critical and can be a silent killer - both for quality and bandwidth.
All surveillance video is compressed, regardless of resolution. And, even if two cameras have the same resolution, their compression levels can be very different (see our Video Quality / Compression Tutorial for more background).
Thankfully, compression in H.264 and H.265 is standardized on a scale of 0 to 51, called quantization, as shown in the image below:
However, camera manufacturers almost never disclose what quantization levels their cameras use. Instead, they use a variety of scales and naming systems. For example, here is what 10 manufacturers refer to their compression settings as:
As a result, two manufacturers' cameras might have the same resolution but significantly different compression levels, and therefore varying image quality and bandwidth consumption.
Average Default Quantization: ~25
Based on stream analysis of 20+ cameras from these 10 manufacturers, we found defaults shown in the chart below.
- Average default quantization level was 25 with a range of 20 to 30.
- Arecont cameras defaulted to the lowest quantization of all cameras tested at Q20, with Panasonic and Uniview close at 21.
- The highest default quantization was Bosch, approximately 30Q by default.
Terminology Differences
None of the manufacturers tested used terminology or scales which easily and directly correlated to other manufacturers. This may cause confusion when trying to standardize multiple cameras at one quantization level.
Further, scales may mean different things depending on the manufacturer, making settings even more confusing. For example, despite all using a numerical scale, Dahua and Sony have high Q levels/lower quality when compression is set to "1", while Avigilon, Axis, and Bosch, have low Q levels/higher quality with compression set closer to "1".
Normalizing Compression
We also normalized each camera's compression settings to achieve a quantization of ~28. This can be useful for users wanting to normalize compression settings on their own cameras, acting as a guide for similar models from the same manufacturer.
Note that while the vast majority of cameras allow users to manually adjust compression settings, there are some exceptions. For example, new generation Hanwha and Sony cameras both include a non-standard VBR implementation which does not fix compression but instead uses only a bitrate target and/or cap, with compression and bitrate both varying. See our report Sony and Samsung Breaking VBR.
Quantization Approximately Similar Using H.265
Based on our tests of multiple manufacturers' cameras, default and standardized quantization levels were approximately similar when using both H.264 and H.265, although bitrates were notably lower in H.265 streams, generally 30-40%. Readers should see our H.265 / HEVC Codec Tutorial 2017 for more information.
Compression Impact on Bandwidth
Bandwidth is strongly impacted by quantization level. To demonstrate this, with adjusted quantization from a baseline of Q35 (highly compressed) to a more typical Q28, followed by a lower compression Q22.
Based on these tests, we found:
- Q35 to Q28: Changing quantization from Q34 to Q28 resulted in a 3x-5x bandwidth increase on cameras tested (Axis, Dahua, Hikvision, Panasonic).
- Q36 to Q22: Changing from Q35 to Q22 resulted in drastic increases, ranging from about 5x to 11x, depending on manufacturer.
Smart Codec Impact
The standardizations discussed above apply only when smart codecs are turned off or not available. By nature, since they adjust quantization dynamically based on objects in the scene instead of adjusting it on the entire image, smart codecs are very difficult, if not impossible, to standardize.
Additionally, quantization levels on smart codec cameras are typically very high, 30+, since much of most scenes is regarded as static background and therefore more highly compressed, with only moving objects remaining average or lower compression.
For example, Axis, Bosch, and Vivotek defaulted to smart codecs enabled in our tests, and all three averaged 30 or higher quantization:
Readers should see our Smart Codec Guide for more details on these features and related issues.
Setting Compression for Different Cameras
Below we show compression settings for each manufacturers' cameras, with notes regarding defaults and optimizations.
Arecont
Arecont is one of few manufacturers to directly use the quantization scale in their web interface. Quantization is adjustable from 16 to 36, defaulting to 20.
Avigilon
Avigilon's compression settings can be changed under the compression and image rate tab in their web UI, and it uses a quality scaled of "1" (lowest compression) to "20" (highest compression). Quality defaults to "6", about 24 quantization.
Axis
Axis currently uses two different web interfaces, as many of their cameras have not yet transitioned to their new HTML5 based UI. Both new and old web UIs default to the same settings: 30 compression. The new web interface uses a slider/manual entry:
While the old interface simply allows free entry:
Bosch
Bosch's codec setup bases quantization on P-frames, with I-frames allowed to vary by a specific amount ("I/P-frame delta QP" below). To standardize to roughly 28Q, users should set "Min. P-frame QP" to 26, and the I/P-frame delta to 0.
Dahua
Dahua's compression settings are found in the video tab, and the "quality" can be set between "1" (most compression) to "6" (least compression), with 2 equating to ~28 quantization on most models tested.
Hikvision
Hikvision's compression settings are under the video/audio tab, on a scale of "lowest" (most compression) to "highest" (least compression), defaulting to "Higher." Based on our tests of multiple Hikvision models, "Medium" equates to ~28Q.
Hanwha/Samsung
New model Hanwha cameras do not include any way to fix compression of the camera, with both bitrate and quantization varying. For full details, see our report Sony and Samsung Breaking VBR.
Older models (Wisenet III/Lite) include compression on a scale from "best (1)" (least compressed) to "worst (20)" (most compressed), defaulting to 4. These models should be set to ~12 on this scale for average 28 quantization.
Panasonic
In order to adjust image quality of Panasonic models, users should set transmission priority to VBR (defaults to Frame rate). Image quality is adjusted on a scale of 0-9 (Super Fine to Low), defaulting to 5 (Normal), with 3 roughly quantization 28.
Note that of cameras tested, Panasonic's new Extreme series were the only models which defaulted to H.265, shown below.
Sony
In Sony 5th/6th gen video codec settings, compression is set in the "Image quality 1: dropdown menu, which ranges from "1" (more compressed) to "10" (less compressed), defaulting to 6 (roughly 28Q).
Note that similar to Hanwha, Sony's 7th gen cameras do not allow compression to be fixed to a set level. See Sony and Samsung Breaking VBR for more details.
Uniview
Uniview cameras show image quality on a slider ranging from simply "Quality" to "Bit Rate", with no option to manually enter a value. The slider should be set to ~3/4 of the way toward Bit Rate for ~28Q.
Vivotek
Vivotek's compression control is named "Target Quality", shown below, with a scale of "Medium" (worst) to "Excellent" (best). "Good" should be used for quantization ~28.
Test Yourself
After reading this report, you should be able to answer all 7 questions on this quiz.
[NOTE: This report was originally published in 2014 and substantially updated in 2017]