[FFmpeg-devel] [PATCH 4/6] avformat/argo_asf: add version_major and version_minor options

[Alexander Strasser]

Hi Zane!


Am 8. August 2020 10:01:07 MESZ schrieb Zane van Iperen <zane at zanevaniperen.com>:
>Signed-off-by: Zane van Iperen <zane at zanevaniperen.com>
>---
> libavformat/argo_asf.c | 37 +++++++++++++++++++++++++++++++++++--
> 1 file changed, 35 insertions(+), 2 deletions(-)
>
>diff --git a/libavformat/argo_asf.c b/libavformat/argo_asf.c
>index 1770192aad..9845cb955b 100644
>--- a/libavformat/argo_asf.c
>+++ b/libavformat/argo_asf.c
>@@ -23,6 +23,7 @@
> #include "internal.h"
> #include "libavutil/intreadwrite.h"
> #include "libavutil/avassert.h"
>+#include "libavutil/opt.h"
> 
> #define ASF_TAG                 MKTAG('A', 'S', 'F', '\0')
> #define ASF_FILE_HEADER_SIZE    24
>@@ -64,6 +65,7 @@ enum {
> };
> 
> typedef struct ArgoASFContext {
>+    const AVClass      *class;
>     ArgoASFFileHeader   fhdr;
>     ArgoASFChunkHeader  ckhdr;
>     uint32_t            blocks_read;
>@@ -296,8 +298,7 @@ static int argo_asf_write_header(AVFormatContext
>*s)
>     ArgoASFContext          *ctx = s->priv_data;
> 
>     ctx->fhdr.magic              = ASF_TAG;
>-    ctx->fhdr.version_major      = 2;
>-    ctx->fhdr.version_minor      = 1;
>+    /* version_{major,minor} set by options. */

Stupid question: Why are you adding options to override the file format version?

Normally those versions have implications on  the syntax and/or semantics of the files they are embedded in.

Am I misreading or misunderstanding something?


>     ctx->fhdr.num_chunks         = 1;
>     ctx->fhdr.chunk_offset       = ASF_FILE_HEADER_SIZE;
>strncpy(ctx->fhdr.name, av_basename(s->url),
>FF_ARRAY_ELEMS(ctx->fhdr.name));
>@@ -340,6 +341,37 @@ static int argo_asf_write_trailer(AVFormatContext
>*s)
>     return 0;
> }
> 
>+static const AVOption argo_asf_options[] = {
>+    {
>+        .name        = "version_major",
>+        .help        = "set file major version",
>+        .offset      = offsetof(ArgoASFContext, fhdr.version_major),
>+        .type        = AV_OPT_TYPE_INT,
>+        .default_val = {.i64 = 2},
>+        .min         = 0,
>+        .max         = UINT16_MAX,
>+        .flags       = AV_OPT_FLAG_ENCODING_PARAM
>+    },
>+    {
>+        .name        = "version_minor",
>+        .help        = "set file minor version",
>+        .offset      = offsetof(ArgoASFContext, fhdr.version_minor),
>+        .type        = AV_OPT_TYPE_INT,
>+        .default_val = {.i64 = 1},
>+        .min         = 0,
>+        .max         = UINT16_MAX,
>+        .flags       = AV_OPT_FLAG_ENCODING_PARAM
>+    },
>+    { NULL }
>+};
>+
>+static const AVClass argo_asf_muxer_class = {
>+    .class_name = "argo_asf_muxer",
>+    .item_name  = av_default_item_name,
>+    .option     = argo_asf_options,
>+    .version    = LIBAVUTIL_VERSION_INT
>+};
>+
> AVOutputFormat ff_argo_asf_muxer = {
>     .name           = "argo_asf",
>     .long_name      = NULL_IF_CONFIG_SMALL("Argonaut Games ASF"),
>@@ -353,6 +385,7 @@ AVOutputFormat ff_argo_asf_muxer = {
>     .write_header   = argo_asf_write_header,
>     .write_packet   = argo_asf_write_packet,
>     .write_trailer  = argo_asf_write_trailer,
>+    .priv_class     = &argo_asf_muxer_class,
>     .priv_data_size = sizeof(ArgoASFContext)
> };
> #endif
>-- 
>2.25.1