The current parser does things which a parser should not, like skipping parts
of the packet header, but it does not actually able to packetize a raw DNXUC
bitstream.
Rework the parser logic to work similar to other parsers and be able to
correctly packetize raw DNXUC bitstreams.
Signed-off-by: Marton Balint <c...@passwd.hu>
---
libavcodec/dnxuc_parser.c | 122 ++++++++++++++------------------------
1 file changed, 44 insertions(+), 78 deletions(-)
diff --git a/libavcodec/dnxuc_parser.c b/libavcodec/dnxuc_parser.c
index 12472c7a2d..14f19efe67 100644
--- a/libavcodec/dnxuc_parser.c
+++ b/libavcodec/dnxuc_parser.c
@@ -20,99 +20,65 @@
*/
/*
- This parser for DNxUncompressed video data is mostly based on
- reverse engineering of output generated by DaVinci Resolve 19
- but was later also checked against the SMPTE RDD 50 specification.
-
- Limitations: Multiple image planes are not supported.
-*/
+ * This parser for DNxUncompressed video data is mostly based on the public
+ * SMPTE RDD 50:2019 specification.
+ */
-#include "avcodec.h"
-#include "libavutil/intreadwrite.h"
+#include "parser.h"
+#include "libavutil/bswap.h"
typedef struct DNxUcParseContext {
- uint32_t fourcc_tag;
- uint32_t width;
- uint32_t height;
- uint32_t nr_bytes;
+ ParseContext pc;
+ uint32_t remaining;
} DNxUcParseContext;
-/*
-DNxUncompressed frame data comes wrapped in nested boxes of metadata
-(box structure: len + fourcc marker + data):
-
-[0-4] len of outer essence unit box (typically 37 bytes of header + frame
data)
-[4-7] fourcc 'pack'
-
-[8-11] len of "signal info box" (always 21)
-[12-15] fourcc 'sinf'
-[16-19] frame width / line packing size
-[20-23] frame hight / nr of lines
-[24-27] fourcc pixel format indicator
-[28] frame_layout (0: progressive, 1: interlaced)
-
-[29-32] len of "signal data box" (nr of frame data bytes + 8)
-[33-36] fourcc 'sdat'
-[37-..] frame data
-
-A sequence of 'signal info'+'signal data' box pairs wrapped in
-'icmp'(=image component) boxes can be utilized to compose more
-complex multi plane images.
-This feature is only partially supported in the present implementation.
-We never pick more than the first pair of info and image data enclosed
-in this way.
-*/
-
static int dnxuc_parse(AVCodecParserContext *s,
AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
- const int HEADER_SIZE = 37;
- int icmp_offset = 0;
-
- DNxUcParseContext *pc;
- pc = (DNxUcParseContext *) s->priv_data;
-
- if (!buf_size) {
- return 0;
- }
- if (buf_size > 16 && MKTAG('i','c','m','p') == AV_RL32(buf+12)){
- icmp_offset += 8;
- }
- if ( buf_size < 37 + icmp_offset /* check metadata structure expectations
*/
- || MKTAG('p','a','c','k') != AV_RL32(buf+4+icmp_offset)
- || MKTAG('s','i','n','f') != AV_RL32(buf+12+icmp_offset)
- || MKTAG('s','d','a','t') != AV_RL32(buf+33+icmp_offset)){
- av_log(avctx, AV_LOG_ERROR, "can't read DNxUncompressed
metadata.\n");
+ DNxUcParseContext *ipc = s->priv_data;
+ int next = END_NOT_FOUND;
+
+ s->pict_type = AV_PICTURE_TYPE_NONE;
+
+ *poutbuf_size = 0;
+ *poutbuf = NULL;
+
+ if (s->flags & PARSER_FLAG_COMPLETE_FRAMES) {
+ next = buf_size;
+ } else {
+ if (ipc->remaining == 0) {
+ uint64_t state = ipc->pc.state64;
+ for (int i = 0; i < buf_size; i++) {
+ state = (state << 8) | buf[i];
+ if (ipc->pc.index + i >= 7 && (uint32_t)state ==
MKBETAG('p','a','c','k')) {
+ uint32_t size = av_bswap32(state >> 32);
+ if (size >= 8) {
+ next = i - 7;
+ ipc->remaining = size + FFMIN(next, 0);
+ break;
+ }
+ }
+ }
+ ipc->pc.state64 = state;
+ } else if (ipc->remaining <= buf_size) {
+ next = ipc->remaining;
+ ipc->remaining = 0;
+ } else {
+ ipc->remaining -= buf_size;
+ }
+ if (ff_combine_frame(&ipc->pc, next, &buf, &buf_size) < 0) {
+ *poutbuf = NULL;
*poutbuf_size = 0;
return buf_size;
+ }
}
- pc->fourcc_tag = AV_RL32(buf+24+icmp_offset);
- pc->width = AV_RL32(buf+16+icmp_offset);
- pc->height = AV_RL32(buf+20+icmp_offset);
- pc->nr_bytes = AV_RL32(buf+29+icmp_offset) - 8;
-
- if (!avctx->codec_tag) {
- av_log(avctx, AV_LOG_INFO, "dnxuc_parser: '%s' %dx%d %dbpp %d\n",
- av_fourcc2str(pc->fourcc_tag),
- pc->width, pc->height,
- (pc->nr_bytes*8)/(pc->width*pc->height),
- pc->nr_bytes);
- avctx->codec_tag = pc->fourcc_tag;
- }
-
- if (pc->nr_bytes > buf_size - HEADER_SIZE + icmp_offset){
- av_log(avctx, AV_LOG_ERROR, "Insufficient size of image essence
data.\n");
- *poutbuf_size = 0;
- return buf_size;
- }
-
- *poutbuf = buf + HEADER_SIZE + icmp_offset;
- *poutbuf_size = pc->nr_bytes;
+ *poutbuf = buf;
+ *poutbuf_size = buf_size;
- return buf_size;
+ return next;
}
const AVCodecParser ff_dnxuc_parser = {
--
2.43.0
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