MPEG-4, also known as H.264 or Advanced Video Coding (AVC), has been in the video compression world since its standardization in 2003. It has transformed the way video content is compressed, transmitted, and stored to deliver better compression efficiency and flexibility than its older versions, such as MPEG-2.
However, with the increasing popularity of video consumption among audiences and the emergence of streaming services, the demand for higher video resolutions is increasing these days. And that further develops the need for more advanced video compression technologies. MPEG-4 continues to play a vital role in fulfilling such demands, but with the release of other standards such as H.265, AV1, or JPEG XS, it faces both opportunities and challenges.
In this article, we will try to give you a detailed guide about MPEG-4/H.264, exploring its working techniques, applications, and comparison with the latest standards. We will also give you a brief on its pros and cons and insights into why it still remains one of the most adopted codecs in the tech world.
What is the MPEG-4/ H.264 Format?
The MPEG-4/H.264 was first introduced by the Joint Video Team (JVT), a partnership between the Moving Picture Experts Group (MPEG) and the International Telecommunication Union’s Video Coding Experts Group (VCEG). The goal was to offer users high-quality video using modern compression technology. The H.264, also known as Advanced Video Coding (AVC), is famous for a variety of applications such as video streaming, video conferencing, and digital television broadcasting—all because of its ability to deliver HD quality video at lower bitrates as well as its compatibility with a wide range of devices and platforms.
How Does The MPEG-4/ H.264 Codec Function?
The H.264 video encoder performs three key tasks—prediction, transformation, and encoding. The aim is to generate a compressed H.264 bitstream. The decoder further reverses these steps by decoding, inverse transformation, and reconstruction to restore the video stream. Let’s dive into the encoder’s processes,
Prediction: Here, the encoder estimates the current frame by examining the previous one, particularly the one preceding it. This technique works on the idea that consecutive frames typically share similar content, such as a static background with moving objects in the foreground. So, instead of encoding the entire current frame, the encoder only transmits the difference between the predicted frame and the actual frame.
Transformation: Using mathematical techniques, the prediction error, which is the difference between the predicted and actual frames, decomposes into smaller spatial components. This breakdown facilitates more efficient data storage and manipulation. It is like dividing an image into small blocks and encoding the color variations within each block.
Quantization: The encoder discards less critical data to compress the file size further. The method strikes a balance between reducing the file size as well as preserving the video quality.
Entropy Encoding: The remaining data is then encoded using specialized algorithms to minimize the number of bits required for representation. This process is similar to how Huffman coding reduces file sizes in compressed files like ZIP archives.
On the decoding side, the process reverses the steps taken by the encoder. First, entropy coding decodes the compressed bitstream into its quantized form. Next, this quantized data undergoes an inverse transformation to convert it back into its original spatial domain. And in the final step, the predicted frame is combined with the decoded data to reconstruct the original video frame through Reconstruction.
Applications of MPEG/H.264
Streaming Services: MPEG/H.264 is the backbone of several popular streaming platforms such as YouTube, Amazon Prime Video, Netflix and Twitch. Its ability to offer high-quality video along with low bit rates makes it a perfect solution for streaming over the internet, where bandwidth constraints vary significantly.
Broadcast Television: The codec usage in broadcast television is pretty significant. It enables transmitting HD content over terrestrial, satellite, and cable networks. Broadcasts rely on H.264’s efficiency, which allows them to deliver high-quality video without depending on excessive bandwidth.
Video Conferencing: H.264 is a standard in video conferencing applications and is famous for providing video communication even over less-than-ideal networks. Its error resilience and network adaption make it a valuable tool for video conferencing applications like Google Meet, Skye, and Zoom.
Blu-ray Discs and Digital Downloads: MPEG-4 is a good standard for Blu-ray discs and many digital downloads due to its high compression ratio and excellent video quality. It allows the storage of large amounts of video content on relatively small media.
Security & Surveillance: H.264's role in security and surveillance is significant because it offers longer recording times and high-quality video while reducing storage requirements. This feature is crucial for applications where a continuous monitoring and recording system is necessary.
Video Recording & Editing: H.264 is widely used in cameras and smartphones for video recording because it balances compression efficiency and quality retention well. It makes the storing, managing, and video editing process seamless across different software and devices.
Action Camera & Drones: H.264 is a preferred video compression format for drones and action cameras due to its ability to deliver a high compression ratio while managing quality output.
What are the advantages of using MPEG-4/H.264?
Offering High Compression Efficiency: H.264 has come up with significant compression efficiency improvements compared to the older standards. It allows for the compression of video files to much smaller sizes while retaining high quality, thus reducing the required bandwidth and storage.
Versatility Across Networks & Devices: H.264 is designed to be highly flexible, enabling it to function effectively across various network environments and devices. It includes features that optimize video streaming even under fluctuating network conditions.
High-quality Video with Low Bitrates: Video quality does not suffer too much when streaming over limited bandwidth networks and is especially efficient at low bit rates. This makes it an excellent choice for mobile streaming and other conditions under restricted bandwidth.
Error Resilience: The codec has features that boost its resilience to errors and packet loss. We have often seen this issue in less reliable networks like mobile data. However, its error resilience contributes to a smoother viewing by minimizing the impact of network-related hurdles.
Extensive Compatibility: MPEG-4 offers widespread support across most software and hardware platforms, including web browsers, tablets, smartphones, and video conferencing systems. Its broader compatibility ensures seamless playback of H.264 encoded videos on nearly any device.
Supporting HD and UHD Resolutions: H.264 supports resolutions of up to 8k, making it suitable for HD, Full HD, and even Ultra High Definition (UHD) video. This efficiency is useful for modern television broadcasts and online video platforms that deliver high-resolution streaming.
What are the disadvantages of using MPEG-4/H.264?
Higher Latency: Compared to newer standards like JPEG XS and JPEG 2000, MPEG-4 introduces more latency, making it less suitable for real-time applications such as VR or Live Streaming.
Compression Trade-offs: While H.264 offers high compression efficiency, it loses quality, particularly at lower bit rates. This trade-off may be a big drawback for sectors where image fidelity is vital.
Computational Demands: H.264 uses advanced techniques that require more inter-frame compression power, which creates restrictions in environments with limited processing resources.
Other Alternatives: With the popularity of new standards like JPG XS or JPEG 2000, H.264 faces increasing competition. This is especially true for applications where high-quality images are paramount, like medical imaging, VR, and digital cinema.
MPEG-4/H.264 vs. Other Video Encodings
There are different types of standards available on the market, but the most common comparisons of MPEG-4 are with H.265, AV1 and VP9. So, let’s discuss each of them and find out which one suits your needs.
H.264 vs. H.265: They are the most common and widely used video compression standards. They can reduce the video file size without compromising the quality and also make it easy to store, transmit and stream video content.
First introduced in 2013, H.265 (HEVC or High-Efficiency Video Coding) is the successor to H.264. Compared to H.264, H.265 offers users better compression efficiency, enabling video encoded at a similar quality but with lower bit rates. Thus, it is suitable for situations where bandwidth is restricted. For instance, you can use H.265 to encode 4K and 8K ultra high-definition video in a comparatively smaller size.
Both can provide high-quality video, but HEVC offers a noticeable improvement in compression efficiency. That means HEVC offers high-quality video even at lower bit rates—perfect for limited bandwidth applications.
However, you may face one challenge with H.265. It requires more processing power for encoding and decoding than H.264, so it will not be suitable for devices with limited processing power. In addition, the licensing cost is also high for H.265 in comparison to H.264.
If we compare these two, H.264 is much more supported than H.265 due to its longer time in the market and its presence across a wide range of devices. However, H.265 is also gaining popularity, leading to an increasing level of support.
AV1: Released by the Alliance for Open Media (AOM), AV1 is the advanced video coding format representing the next generation of codecs. It enhances the HEVC’s encoding and decoding capabilities by 30%, requiring less computational power and rapid hardware optimizations. With that, AV1 delivers top-quality real-time video that you can scale across any device. Featuring highly advanced algorithms, AV1 is best suited for WebRTC and HTML5 Web Video, often paired with Opus audio codec.
VP9: Introduced by Google, VP9 is a royalty-free alternative to H.265. It is widely supported across all Google-connected video platforms, including Chrome Browser, YouTube, and Android. VP9 offers users better video quality at the same bitrate level as H.264. This makes it suitable for video streaming and delivering 4k HD videos online.
Comparing H.264 with H.265, AV1 and VP9
When comparing H. 264 to other video compressions, you should know it is an older codec. With the rapid advancement of technology, newer versions have emerged to address more complex and specialized challenges. Despite all this, each codec, whether we are talking about the older H.264 or the more modern H.265 or the AV1, has relevant use cases and depending on your device and bandwidth constraints, you can choose the one that fits your requirements.
How do you decide which video compression will fit your needs?
Consider H.264: If device compatibility and limited bandwidth are your top priorities, or if you are looking for a widely supported and reliable codec, try H. 264.
Go with the Newer Version: When you stream high-resolution content (4K or higher), compatibility with older devices is not a big issue. Additionally, you have the processing power to manage more complex encoding tasks.
What does the future hold for MPEG-4/H.264?
Indeed, with the emergence of newer video compression standards, MPEG-4/H.264's market is becoming a bit competitive, but its relevance will remain the same in upcoming years. Its widespread adaptation, extensive software and hardware compatibility and proven track record make it a trustworthy video compression for many applications and sectors. However, developing more advanced codecs such as HEVC, AV1, and JPEG will likely supplant H.264 in specific applications as demand for higher resolution, lower latency, and better compression increases.
However, H.264 will remain dominant in one area: the sectors where compatibility and legacy support are vital. Many devices, such as smartphones, tablets, and televisions, are designed with H.264 in mind, so replacing them with newer versions requires major infrastructure changes. In addition to that, with its high efficiency and versatility, H.264 continues to make it a good contender in the world of streaming, broadcasting or video conferencing. It’s good in such fields where maintaining a good balance between quality, performance, and compression is necessary.
