avcodec/h2645_sei: use named constants for ITU-T T.35 metadata

Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/h2645_sei.c

@@ -40,6 +40,7 @@
 #include "get_bits.h"
 #include "golomb.h"
 #include "h2645_sei.h"
+#include "itut35.h"
 
 #define IS_H264(codec_id) (CONFIG_H264_SEI && CONFIG_HEVC_SEI ? codec_id == AV_CODEC_ID_H264 : CONFIG_H264_SEI)
 #define IS_HEVC(codec_id) (CONFIG_H264_SEI && CONFIG_HEVC_SEI ? codec_id == AV_CODEC_ID_HEVC : CONFIG_HEVC_SEI)
@@ -140,7 +141,8 @@ static int decode_registered_user_data(H2645SEI *h, GetByteContext *gb,
         bytestream2_skipu(gb, 1);  // itu_t_t35_country_code_extension_byte
     }
 
-    if (country_code != 0xB5 && country_code != 0x26) { // usa_country_code and cn_country_code
+    if (country_code != ITU_T_T35_COUNTRY_CODE_US &&
+        country_code != ITU_T_T35_COUNTRY_CODE_CN) {
         av_log(logctx, AV_LOG_VERBOSE,
                "Unsupported User Data Registered ITU-T T35 SEI message (country_code = %d)\n",
                country_code);
@@ -151,7 +153,7 @@ static int decode_registered_user_data(H2645SEI *h, GetByteContext *gb,
     provider_code = bytestream2_get_be16u(gb);
 
     switch (provider_code) {
-    case 0x31: { // atsc_provider_code
+    case ITU_T_T35_PROVIDER_CODE_ATSC: {
         uint32_t user_identifier;
 
         if (bytestream2_get_bytes_left(gb) < 4)
@@ -172,7 +174,7 @@ static int decode_registered_user_data(H2645SEI *h, GetByteContext *gb,
         break;
     }
 #if CONFIG_HEVC_SEI
-    case 0x04: { // cuva_provider_code
+    case ITU_T_T35_PROVIDER_CODE_CUVA: {
         const uint16_t cuva_provider_oriented_code = 0x0005;
         uint16_t provider_oriented_code;
 
@@ -188,7 +190,7 @@ static int decode_registered_user_data(H2645SEI *h, GetByteContext *gb,
         }
         break;
     }
-    case 0x3C: { // smpte_provider_code
+    case ITU_T_T35_PROVIDER_CODE_SMTPE: {
         // A/341 Amendment - 2094-40
         const uint16_t smpte2094_40_provider_oriented_code = 0x0001;
         const uint8_t smpte2094_40_application_identifier = 0x04;

libavcodec/itut35.h

@@ -19,9 +19,11 @@
 #ifndef AVCODEC_ITUT35_H
 #define AVCODEC_ITUT35_H
 
+#define ITU_T_T35_COUNTRY_CODE_CN 0x26
 #define ITU_T_T35_COUNTRY_CODE_US 0xB5
 
 #define ITU_T_T35_PROVIDER_CODE_ATSC  0x31
+#define ITU_T_T35_PROVIDER_CODE_CUVA  0x04
 #define ITU_T_T35_PROVIDER_CODE_DOLBY 0x3B
 #define ITU_T_T35_PROVIDER_CODE_SMTPE 0x3C