Looking at the full year, we had a strong fiscal 2021 with 10% revenue growth and our highest operating margin since fiscal 2014, and we created considerable momentum across many of our growth initiatives, that will allow more people to be entertained by premium Dolby experiences.
Let's start with our foundational audio technologies, which include Dolby Digital Plus, AC-4 and our audio patent licensing.
In FY '21, our foundational audio technologies grew about 11% year-over-year, due largely to robust global shipments of DCs and higher TV volumes, particularly in North America and Europe.
In total, this portion is approaching one quarter of our licensing revenue and grew nearly 20% in FY '21.
We see this growth accelerating to over 35% in FY '22.
This quarter, the launch of the iPhone 13 lineup again highlighted the capability to enable consumers to record and share their videos in Dolby Vision.
And collectively, we estimate the addressable market to be about $5 billion and growing.
Total revenue in the fourth quarter was $285 million, which was within the total revenue guidance range we provided, and also included a favorable true-up of about $3 million for Q3 shipments reported, that were above the original estimate.
With our Q4 results, full year 2021 revenues were $1.28 billion compared to $1.16 billion in fiscal year 2020, generating 10% year-over-year growth.
Within that, licensing revenue was $1.21 billion, while products and services revenue was $67 million.
On a year-over-year basis, fourth quarter revenue was about $14 million above last year's Q4, as we benefited from greater adoption of Dolby Vision and Dolby Atmos and higher cinema-related revenues, partially offset by lower true-ups.
Q4 revenue was comprised of $266 million in licensing and $19 million in Products and services.
Broadcast represented about 39% of the total licensing in fiscal year 2021.
Our full year revenues grew by $36 million or 8% on a year-over-year basis, driven by higher adoption of Dolby Vision and Dolby Atmos in TVs and set-top boxes.
Mobile represented approximately 22% of total licensing in fiscal 2021.
Mobile revenue increased by $34 million or 15% compared to fiscal 2020, as our foundational audio revenues benefited from timing of revenues, and we saw higher Dolby Vision revenues from increased adoption.
Our Q4 mobile revenues were up about 2% compared to the prior year, due to higher adoption of Dolby Vision and Dolby Atmos.
Consumer electronics represented about 15% of total licensing in fiscal year 2021.
On a year-over-year basis, CE licensing increased by $29 million or 19%, driven by higher foundational audio revenues, as a result of increased unit volumes in soundbars and AVRs, as well as higher recoveries.
Our Q4 CE revenues increased 28% compared to prior year, which was in line with full year growth drivers of both higher foundational audio revenues and growing adoption of Dolby Atmos and Dolby Vision.
PC represented about 12% of total licensing in fiscal year 2021.
Our fiscal year '21 PC revenues were higher than prior year by about $10 million or 7%, driven by higher foundational audio revenues, as a result of strong PC shipments throughout the year and growing revenues from Dolby Atmos and Dolby Vision.
Our Q4 PC revenues were about 7% higher compared to prior year Q4, driven by increased Dolby Vision and Dolby Atmos revenues.
Other markets represent about 12% of total licensing in fiscal year 2021.
They were up about $26 million or 21% year-over-year, driven by higher revenues from gaming, due to the console refresh cycle and higher foundational revenues related to patents.
In Q4, we saw other markets grow about 26% year-over-year due to increased Dolby Cinema revenues as theaters reopen, and higher revenues from gaming.
As we look ahead to fiscal '22, we anticipate that other markets revenues could grow at an even higher rate of over 25%, as we estimate Dolby Cinema revenues to continue momentum from Q4, as more people are able to return to the movies and we also see continued growth in gaming.
Beyond licensing, our products and services revenue was $67 million in fiscal year '21, compared to $83 million in fiscal year 2020.
Products and services revenue in Q4 was $19 million compared to $14 million in last year's Q4.
Total gross margin in the fourth quarter was 89.2% on a GAAP basis and 90% on a non-GAAP basis.
Operating expenses in the fourth quarter on a GAAP basis were $214 million.
Operating expenses in the fourth quarter on a non-GAAP basis were $189.9 million, compared to $176.5 million in the prior year.
Operating income in the fourth quarter was $40.4 million on a GAAP basis or 14.2% of revenue, compared to $30.1 million or 11.1% of revenue in Q4 of last year.
Operating income in the fourth quarter on a non-GAAP basis was $66.6 million or 23.4% of revenue, compared to $54.3 million or 20% of revenue in Q4 of last year.
On a full year basis, operating income was $344.4 million on a GAAP basis or about 26.9% of revenue, compared to $218.7 million or 18.8% in fiscal 2020.
Full year operating income in fiscal '21 on a non-GAAP basis was $450.7 million or about 35.2% of revenue compared to $317.9 million or 27.4% in the prior year.
Income tax in Q4 was minus 3% on a GAAP basis and 13% on a non-GAAP basis.
Net income on a GAAP basis in the fourth quarter was $44.2 million or $0.42 per diluted share compared to $26.8 million or $0.26 per diluted share in last year's Q4.
Net income on a non-GAAP basis in the fourth quarter was $60.4 million or $0.58 per diluted share, compared to $45.8 million or $0.45 per diluted share in Q4 of last year.
During the fourth quarter, we generated $110 million in cash from operations compared to $113 million generated in last year's fourth quarter.
We ended the fourth quarter with about $1.3 billion in cash and investments.
During the fourth quarter, we bought back about 1 million shares of our common stock and ended the quarter with about $291 million of stock repurchase authorization available going forward.
We also announced today a cash dividend of $0.25 per share, an increase of $0.03 or 14% compared to the prior quarter.
We currently estimate total fiscal year '22 revenues could range from $1.34 billion to $1.4 billion.
This would result in about 5% to 9% of year-over-year growth as compared to the $1.28 billion in fiscal year 2021.
Within this, licensing revenue could range from $1.260 billion to $1.315 billion compared to $1.214 billion in fiscal year '21, which would result in a 4% to 8% year-over-year growth.
For products and services revenues, we anticipate this could range from $75 million to $90 million for fiscal year '22, with improvements in cinema products and growth in Dolby.io.
With these considerations, we are estimating operating expenses for fiscal 2022 could range from $869 million to $889 million on a GAAP basis and between $750 million to $770 million on a non-GAAP basis.
With all of this, our business model remains very strong, as we expect to deliver operating margins between 24% to 26% on a GAAP basis, and between 34% and 36% on a non-GAAP basis.
Based on the factors above, we estimate that full year diluted earnings per share will range from $2.53 to $3.03 on a GAAP basis and $3.52 to $4.02 on a non-GAAP basis.
For Q1, we see total revenues ranging from $345 million to $375 million.
Within that, licensing revenues will range from $330 million to $355 million.
Note that in the prior year Q1, we benefited from a significant favorable true-up of over $21 million for Q4 fiscal '20 shipments, that was larger than normal, given the volatility of conditions during the pandemic.
Q1 products and services revenue could range from $15 million to $20 million.
Q1 gross margin on a GAAP basis is expected to be 90% to 91%, and the non-GAAP gross margin is estimated to be about 91% to 92%.
Operating expenses in Q1 on a GAAP basis are estimated to range from $221 million to $231 million.
Operating expenses in Q1 on a non-GAAP basis are estimated to range from $190 million to $200 million, which contemplates the impact of the 53-week fiscal year.
Other income is projected to range from $1 million to $2 million for the first quarter.
And our effective tax rate for Q1 is projected to range from 18% to 19% on both a GAAP and non-GAAP basis.
Based on the combination of the factors I just covered, we estimate that Q1 diluted earnings per share could range from $0.71 to $0.86 on a GAAP basis and from $0.98 to $1.13 on a non-GAAP basis.

Summary:
Total revenue in the fourth quarter was $285 million, which was within the total revenue guidance range we provided, and also included a favorable true-up of about $3 million for Q3 shipments reported, that were above the original estimate.
Net income on a GAAP basis in the fourth quarter was $44.2 million or $0.42 per diluted share compared to $26.8 million or $0.26 per diluted share in last year's Q4.
Net income on a non-GAAP basis in the fourth quarter was $60.4 million or $0.58 per diluted share, compared to $45.8 million or $0.45 per diluted share in Q4 of last year.
We currently estimate total fiscal year '22 revenues could range from $1.34 billion to $1.4 billion.
Based on the factors above, we estimate that full year diluted earnings per share will range from $2.53 to $3.03 on a GAAP basis and $3.52 to $4.02 on a non-GAAP basis.
For Q1, we see total revenues ranging from $345 million to $375 million.
Based on the combination of the factors I just covered, we estimate that Q1 diluted earnings per share could range from $0.71 to $0.86 on a GAAP basis and from $0.98 to $1.13 on a non-GAAP basis.