| // Copyright 2018 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "media/video/h264_level_limits.h" |
| |
| #include "base/logging.h" |
| #include "media/video/h264_parser.h" |
| |
| namespace media { |
| namespace { |
| struct LevelLimits { |
| // All names and abbreviations are as in table A-1 in spec. |
| // MaxMBPS, Max. macroblock processing rate (MB/s) |
| uint32_t max_mbps; |
| // MaxFS, Max. frame size (MBs) |
| uint32_t max_fs; |
| // MaxDpbMbs, Max. decoded picture buffer size (MBs) |
| uint32_t max_dpb_mbs; |
| // MaxBR, Max. video bitrate for Baseline and Main Profiles (kbit/s) |
| uint32_t max_main_br; |
| }; |
| |
| LevelLimits LevelToLevelLimits(uint8_t level) { |
| // See table A-1 in spec |
| // { MaxMBPS, MaxFS, MaxDpbMbs, MaxBR} |
| switch (level) { |
| case H264SPS::kLevelIDC1p0: |
| return {1485, 99, 396, 64}; // Level 1.0 |
| case H264SPS::kLevelIDC1B: |
| return {1485, 99, 396, 128}; // Level 1b |
| case H264SPS::kLevelIDC1p1: |
| return {3000, 396, 900, 192}; // Level 1.1 |
| case H264SPS::kLevelIDC1p2: |
| return {6000, 396, 2376, 384}; // Level 1.2 |
| case H264SPS::kLevelIDC1p3: |
| return {11800, 396, 2376, 768}; // Level 1.3 |
| case H264SPS::kLevelIDC2p0: |
| return {11880, 396, 2376, 2000}; // Level 2.0 |
| case H264SPS::kLevelIDC2p1: |
| return {19800, 792, 4752, 4000}; // Level 2.1 |
| case H264SPS::kLevelIDC2p2: |
| return {20250, 1620, 8100, 4000}; // Level 2.2 |
| case H264SPS::kLevelIDC3p0: |
| return {40500, 1620, 8100, 10000}; // Level 3.0 |
| case H264SPS::kLevelIDC3p1: |
| return {108000, 3600, 18000, 14000}; // Level 3.1 |
| case H264SPS::kLevelIDC3p2: |
| return {216000, 5120, 20480, 20000}; // Level 3.2 |
| case H264SPS::kLevelIDC4p0: |
| return {245760, 8192, 32768, 20000}; // Level 4.0 |
| case H264SPS::kLevelIDC4p1: |
| return {245760, 8192, 32768, 50000}; // Level 4.1 |
| case H264SPS::kLevelIDC4p2: |
| return {522240, 8704, 34816, 50000}; // Level 4.2 |
| case H264SPS::kLevelIDC5p0: |
| return {589824, 22080, 110400, 135000}; // Level 5.0 |
| case H264SPS::kLevelIDC5p1: |
| return {983040, 36864, 184320, 240000}; // Level 5.1 |
| case H264SPS::kLevelIDC5p2: |
| return {2073600, 36864, 184320, 240000}; // Level 5.2 |
| case H264SPS::kLevelIDC6p0: |
| return {4177920, 139264, 696320, 240000}; // Level 6.0 |
| case H264SPS::kLevelIDC6p1: |
| return {8355840, 139264, 696320, 480000}; // Level 6.1 |
| case H264SPS::kLevelIDC6p2: |
| return {16711680, 139264, 696320, 800000}; // Level 6.2 |
| default: |
| DVLOG(1) << "Invalid codec level (" << static_cast<int>(level) << ")"; |
| return {0, 0, 0, 0}; |
| } |
| } |
| } // namespace |
| |
| uint32_t H264LevelToMaxMBPS(uint8_t level) { |
| return LevelToLevelLimits(level).max_mbps; |
| } |
| |
| uint32_t H264LevelToMaxFS(uint8_t level) { |
| return LevelToLevelLimits(level).max_fs; |
| } |
| |
| uint32_t H264LevelToMaxDpbMbs(uint8_t level) { |
| return LevelToLevelLimits(level).max_dpb_mbs; |
| } |
| |
| uint32_t H264ProfileLevelToMaxBR(VideoCodecProfile profile, uint8_t level) { |
| uint32_t max_main_br = LevelToLevelLimits(level).max_main_br; |
| |
| // See table A-2 in spec |
| // The maximum bit rate for High Profile is 1.25 times that of the |
| // Base/Extended/Main Profiles, 3 times for Hi10P, and 4 times for |
| // Hi422P/Hi444PP. |
| switch (profile) { |
| case H264PROFILE_BASELINE: |
| case H264PROFILE_MAIN: |
| case H264PROFILE_EXTENDED: |
| return max_main_br; |
| case H264PROFILE_HIGH: |
| return max_main_br * 5 / 4; |
| case H264PROFILE_HIGH10PROFILE: |
| return max_main_br * 3; |
| case H264PROFILE_HIGH422PROFILE: |
| case H264PROFILE_HIGH444PREDICTIVEPROFILE: |
| return max_main_br * 4; |
| default: |
| DVLOG(1) << "Failed to query MaxBR for profile: " |
| << GetProfileName(profile); |
| return 0; |
| } |
| } |
| |
| bool CheckH264LevelLimits(VideoCodecProfile profile, |
| uint8_t level, |
| uint32_t bitrate, |
| uint32_t framerate, |
| uint32_t framesize_in_mbs) { |
| uint32_t max_bitrate_kbs = H264ProfileLevelToMaxBR(profile, level); |
| DCHECK(base::IsValueInRangeForNumericType<uint32_t>(max_bitrate_kbs * 1000)); |
| |
| uint32_t max_bitrate = max_bitrate_kbs * 1000; |
| if (bitrate > max_bitrate) { |
| DVLOG(1) << "Target bitrate: " << bitrate << " exceeds Max: " << max_bitrate |
| << " bit/s"; |
| return false; |
| } |
| |
| if (framesize_in_mbs > H264LevelToMaxFS(level)) { |
| DVLOG(1) << "Target frame size: " << framesize_in_mbs |
| << " exceeds Max: " << H264LevelToMaxFS(level) << " Macroblocks"; |
| return false; |
| } |
| |
| uint32_t mbps = framesize_in_mbs * framerate; |
| if (mbps > H264LevelToMaxMBPS(level)) { |
| DVLOG(1) << "Target macroblock processing rate: " << mbps |
| << " exceeds Max: " << H264LevelToMaxMBPS(level) << "Macroblock/s"; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| } // namespace media |