avcodec/av1_metadata_bsf: Use separate contexts for reading/writing

Based on code from 235a5734e0

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

libavcodec/av1_metadata_bsf.c

@@ -33,7 +33,8 @@ enum {
 typedef struct AV1MetadataContext {
     const AVClass *class;
 
-    CodedBitstreamContext *cbc;
+    CodedBitstreamContext *input;
+    CodedBitstreamContext *output;
     CodedBitstreamFragment access_unit;
 
     int td;
@@ -125,7 +126,7 @@ static int av1_metadata_update_side_data(AVBSFContext *bsf, AVPacket *pkt)
     if (!side_data_size)
         return 0;
 
-    err = ff_cbs_read(ctx->cbc, frag, side_data, side_data_size);
+    err = ff_cbs_read(ctx->input, frag, side_data, side_data_size);
     if (err < 0) {
         av_log(bsf, AV_LOG_ERROR, "Failed to read extradata from packet side data.\n");
         return err;
@@ -140,7 +141,7 @@ static int av1_metadata_update_side_data(AVBSFContext *bsf, AVPacket *pkt)
         }
     }
 
-    err = ff_cbs_write_fragment_data(ctx->cbc, frag);
+    err = ff_cbs_write_fragment_data(ctx->output, frag);
     if (err < 0) {
         av_log(bsf, AV_LOG_ERROR, "Failed to write extradata into packet side data.\n");
         return err;
@@ -171,7 +172,7 @@ static int av1_metadata_filter(AVBSFContext *bsf, AVPacket *pkt)
     if (err < 0)
         goto fail;
 
-    err = ff_cbs_read_packet(ctx->cbc, frag, pkt);
+    err = ff_cbs_read_packet(ctx->input, frag, pkt);
     if (err < 0) {
         av_log(bsf, AV_LOG_ERROR, "Failed to read packet.\n");
         goto fail;
@@ -216,7 +217,7 @@ static int av1_metadata_filter(AVBSFContext *bsf, AVPacket *pkt)
         }
     }
 
-    err = ff_cbs_write_packet(ctx->cbc, pkt, frag);
+    err = ff_cbs_write_packet(ctx->output, pkt, frag);
     if (err < 0) {
         av_log(bsf, AV_LOG_ERROR, "Failed to write packet.\n");
         goto fail;
@@ -239,12 +240,15 @@ static int av1_metadata_init(AVBSFContext *bsf)
     AV1RawOBU *obu;
     int err, i;
 
-    err = ff_cbs_init(&ctx->cbc, AV_CODEC_ID_AV1, bsf);
+    err = ff_cbs_init(&ctx->input, AV_CODEC_ID_AV1, bsf);
+    if (err < 0)
+        return err;
+    err = ff_cbs_init(&ctx->output, AV_CODEC_ID_AV1, bsf);
     if (err < 0)
         return err;
 
     if (bsf->par_in->extradata) {
-        err = ff_cbs_read_extradata(ctx->cbc, frag, bsf->par_in);
+        err = ff_cbs_read_extradata(ctx->input, frag, bsf->par_in);
         if (err < 0) {
             av_log(bsf, AV_LOG_ERROR, "Failed to read extradata.\n");
             goto fail;
@@ -259,7 +263,7 @@ static int av1_metadata_init(AVBSFContext *bsf)
             }
         }
 
-        err = ff_cbs_write_extradata(ctx->cbc, bsf->par_out, frag);
+        err = ff_cbs_write_extradata(ctx->output, bsf->par_out, frag);
         if (err < 0) {
             av_log(bsf, AV_LOG_ERROR, "Failed to write extradata.\n");
             goto fail;
@@ -277,7 +281,8 @@ static void av1_metadata_close(AVBSFContext *bsf)
     AV1MetadataContext *ctx = bsf->priv_data;
 
     ff_cbs_fragment_free(&ctx->access_unit);
-    ff_cbs_close(&ctx->cbc);
+    ff_cbs_close(&ctx->input);
+    ff_cbs_close(&ctx->output);
 }
 
 #define OFFSET(x) offsetof(AV1MetadataContext, x)