[FFmpeg-devel] [PATCH] avformat/framecrcenc: support calculating checksum of IAMF side data

[James Almer]

The total allocated size for types is arch dependent, so instead calculate a
checksum of the fields only.

Signed-off-by: James Almer <jamrial at gmail.com>
---
Depends on "[PATCH v3] avformat/framecrcenc: compute the checksum for side data"

 libavformat/framecrcenc.c | 76 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 71 insertions(+), 5 deletions(-)

diff --git a/libavformat/framecrcenc.c b/libavformat/framecrcenc.c
index 8cc4a93053..6d46b51489 100644
--- a/libavformat/framecrcenc.c
+++ b/libavformat/framecrcenc.c
@@ -24,6 +24,7 @@
 #include "config.h"
 #include "libavutil/adler32.h"
 #include "libavutil/avstring.h"
+#include "libavutil/iamf.h"
 #include "libavutil/intreadwrite.h"
 
 #include "libavcodec/codec_id.h"
@@ -76,7 +77,8 @@ static int framecrc_write_packet(struct AVFormatContext *s, AVPacket *pkt)
         for (int i = 0; i < pkt->side_data_elems; i++) {
             const AVPacketSideData *const sd = &pkt->side_data[i];
             const uint8_t *data = sd->data;
-            int64_t side_data_crc = 0;
+            size_t size = sd->size;
+            uint32_t side_data_crc = 0;
 
             switch (sd->type) {
 #if HAVE_BIGENDIAN
@@ -127,12 +129,76 @@ static int framecrc_write_packet(struct AVFormatContext *s, AVPacket *pkt)
             case AV_PKT_DATA_IAMF_MIX_GAIN_PARAM:
             case AV_PKT_DATA_IAMF_DEMIXING_INFO_PARAM:
             case AV_PKT_DATA_IAMF_RECON_GAIN_INFO_PARAM:
-                side_data_crc = -1;
+            {
+                const AVIAMFParamDefinition *param = (AVIAMFParamDefinition *)sd->data;
+                uint8_t buf[8];
+                ptrdiff_t offset = 0;
+                size = 0;
+#define READ_UINT32(struct, parent, child) do { \
+    if ((offset + offsetof(struct, child) + sizeof(parent->child)) > sd->size) \
+        goto iamf_end; \
+    AV_WL32(buf, parent->child); \
+    side_data_crc = av_adler32_update(side_data_crc, buf, 4); \
+    size += 4; \
+} while (0)
+#define READ_RATIONAL(struct, parent, child) do { \
+    if ((offset + offsetof(struct, child) + sizeof(parent->child)) > sd->size) \
+        goto iamf_end; \
+    AV_WL32(buf + 0, parent->child.num); \
+    AV_WL32(buf + 4, parent->child.den); \
+    side_data_crc = av_adler32_update(side_data_crc, buf, 8); \
+    size += 8; \
+} while (0)
+                READ_UINT32(AVIAMFParamDefinition, param, nb_subblocks);
+                READ_UINT32(AVIAMFParamDefinition, param, type);
+                READ_UINT32(AVIAMFParamDefinition, param, parameter_id);
+                READ_UINT32(AVIAMFParamDefinition, param, parameter_rate);
+                READ_UINT32(AVIAMFParamDefinition, param, duration);
+                READ_UINT32(AVIAMFParamDefinition, param, constant_subblock_duration);
+                for (unsigned int i = 0; i < param->nb_subblocks; i++) {
+                    void *subblock = av_iamf_param_definition_get_subblock(param, i);
+
+                    offset = (intptr_t)subblock - (intptr_t)sd->data;
+                    switch (param->type) {
+                    case AV_IAMF_PARAMETER_DEFINITION_MIX_GAIN: {
+                        const AVIAMFMixGain *mix = subblock;
+                        READ_UINT32(AVIAMFMixGain, mix, subblock_duration);
+                        READ_UINT32(AVIAMFMixGain, mix, animation_type);
+                        READ_RATIONAL(AVIAMFMixGain, mix, start_point_value);
+                        READ_RATIONAL(AVIAMFMixGain, mix, end_point_value);
+                        READ_RATIONAL(AVIAMFMixGain, mix, control_point_value);
+                        READ_RATIONAL(AVIAMFMixGain, mix, control_point_relative_time);
+                        break;
+                    }
+                    case AV_IAMF_PARAMETER_DEFINITION_DEMIXING: {
+                        const AVIAMFDemixingInfo *demix = subblock;
+                        READ_UINT32(AVIAMFDemixingInfo, demix, subblock_duration);
+                        READ_UINT32(AVIAMFDemixingInfo, demix, dmixp_mode);
+                        break;
+                    }
+                    case AV_IAMF_PARAMETER_DEFINITION_RECON_GAIN: {
+                        const AVIAMFReconGain *recon = subblock;
+                        READ_UINT32(AVIAMFReconGain, recon, subblock_duration);
+                        if ((offset + offsetof(AVIAMFReconGain, recon_gain)
+                                    + sizeof(recon->recon_gain)) > sd->size)
+                            goto iamf_end;
+                        side_data_crc = av_adler32_update(side_data_crc,
+                                                          (uint8_t *)recon->recon_gain,
+                                                          sizeof(recon->recon_gain));
+                        size += sizeof(recon->recon_gain);
+                        break;
+                    }
+                    default:
+                        break;
+                    }
+                }
+                iamf_end:
+                break;
+            }
             }
 
-            av_strlcatf(buf, sizeof(buf), ", T=%2d, %8"SIZE_SPECIFIER, pkt->side_data[i].type, pkt->side_data[i].size);
-            if (side_data_crc >= 0)
-                av_strlcatf(buf, sizeof(buf), ", 0x%08"PRIx32, (uint32_t)side_data_crc);
+            av_strlcatf(buf, sizeof(buf), ", T=%2d, %8"SIZE_SPECIFIER, pkt->side_data[i].type, size);
+            av_strlcatf(buf, sizeof(buf), ", 0x%08"PRIx32, side_data_crc);
         }
     }
     av_strlcatf(buf, sizeof(buf), "\n");
-- 
2.44.0