[FFmpeg-devel] [PATCH v5] avcodec/libx264: fix extradata when config annexb=0
Zhao Zhili
quinkblack at foxmail.com
Wed Mar 13 15:36:42 EET 2024
From: Zhao Zhili <zhilizhao at tencent.com>
---
v5: Decode chroma_format_idc directly instead of ff_h264_decode_seq_parameter_set
v4: Fix missing SEI in set_avcc_extradata
v3: Remove unnecessary inclusion
libavcodec/libx264.c | 162 ++++++++++++++++++++++++++++++++++++-------
1 file changed, 138 insertions(+), 24 deletions(-)
diff --git a/libavcodec/libx264.c b/libavcodec/libx264.c
index 10d646bd76..64cefb5fb0 100644
--- a/libavcodec/libx264.c
+++ b/libavcodec/libx264.c
@@ -38,6 +38,7 @@
#include "packet_internal.h"
#include "atsc_a53.h"
#include "sei.h"
+#include "golomb.h"
#include <x264.h>
#include <float.h>
@@ -865,6 +866,140 @@ static int convert_pix_fmt(enum AVPixelFormat pix_fmt)
return 0;
}
+static int save_sei(AVCodecContext *avctx, x264_nal_t *nal)
+{
+ X264Context *x4 = avctx->priv_data;
+
+ av_log(avctx, AV_LOG_INFO, "%s\n", nal->p_payload + 25);
+ x4->sei_size = nal->i_payload;
+ x4->sei = av_malloc(x4->sei_size);
+ if (!x4->sei)
+ return AVERROR(ENOMEM);
+
+ memcpy(x4->sei, nal->p_payload, nal->i_payload);
+
+ return 0;
+}
+
+static int set_avcc_extradata(AVCodecContext *avctx, x264_nal_t *nal, int nnal)
+{
+ X264Context *x4 = avctx->priv_data;
+ x264_nal_t *sps_nal = NULL;
+ x264_nal_t *pps_nal = NULL;
+ uint8_t *p, *sps;
+ int ret;
+
+ /* We know it's in the order of SPS/PPS/SEI, but it's not documented in x264 API.
+ * The x264 param i_sps_id implies there is a single pair of SPS/PPS.
+ */
+ for (int i = 0; i < nnal; i++) {
+ switch (nal[i].i_type) {
+ case NAL_SPS:
+ sps_nal = &nal[i];
+ break;
+ case NAL_PPS:
+ pps_nal = &nal[i];
+ break;
+ case NAL_SEI:
+ ret = save_sei(avctx, &nal[i]);
+ if (ret < 0)
+ return ret;
+ break;
+ }
+ }
+ if (!sps_nal || !pps_nal)
+ return AVERROR_EXTERNAL;
+
+ avctx->extradata_size = sps_nal->i_payload + pps_nal->i_payload + 7;
+ avctx->extradata = av_mallocz(avctx->extradata_size + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!avctx->extradata)
+ return AVERROR(ENOMEM);
+
+ // Now create AVCDecoderConfigurationRecord
+ p = avctx->extradata;
+ // Skip size part
+ sps = sps_nal->p_payload + 4;
+ *p++ = 1; // version
+ *p++ = sps[1]; // AVCProfileIndication
+ *p++ = sps[2]; // profile_compatibility
+ *p++ = sps[3]; // AVCLevelIndication
+ *p++ = 0xFF;
+ *p++ = 0xE0 | 0x01; // 3 bits reserved (111) + 5 bits number of sps
+ memcpy(p, sps_nal->p_payload + 2, sps_nal->i_payload - 2);
+ // Make sps has AV_INPUT_BUFFER_PADDING_SIZE padding, so it can be used
+ // with GetBitContext
+ sps = p + 2;
+ p += sps_nal->i_payload - 2;
+ *p++ = 1;
+ memcpy(p, pps_nal->p_payload + 2, pps_nal->i_payload - 2);
+ p += pps_nal->i_payload - 2;
+
+ if (sps[3] != 66 && sps[3] != 77 && sps[3] != 88) {
+ GetBitContext gbc;
+ int chroma_format_idc;
+ int bit_depth_luma_minus8, bit_depth_chroma_minus8;
+
+ /* It's not possible to have emulation prevention byte before
+ * bit_depth_chroma_minus8 due to the range of sps id, chroma_format_idc
+ * and so on. So we can read directly without need to escape emulation
+ * prevention byte.
+ *
+ * +4 to skip until sps id.
+ */
+ init_get_bits8(&gbc, sps + 4, sps_nal->i_payload - 4 - 4);
+ // Skip sps id
+ get_ue_golomb_31(&gbc);
+ chroma_format_idc = get_ue_golomb_31(&gbc);
+ if (chroma_format_idc == 3)
+ skip_bits1(&gbc);
+ bit_depth_luma_minus8 = get_ue_golomb_31(&gbc);
+ bit_depth_chroma_minus8 = get_ue_golomb_31(&gbc);
+
+ *p++ = 0xFC | chroma_format_idc;
+ *p++ = 0xF8 | bit_depth_luma_minus8;
+ *p++ = 0xF8 | bit_depth_chroma_minus8;
+ *p++ = 0;
+ }
+ av_assert0(avctx->extradata + avctx->extradata_size >= p);
+ avctx->extradata_size = p - avctx->extradata;
+
+ return 0;
+}
+
+static int set_extradata(AVCodecContext *avctx)
+{
+ X264Context *x4 = avctx->priv_data;
+ x264_nal_t *nal;
+ uint8_t *p;
+ int nnal, s;
+
+ s = x264_encoder_headers(x4->enc, &nal, &nnal);
+ if (s < 0)
+ return AVERROR_EXTERNAL;
+
+ if (!x4->params.b_annexb)
+ return set_avcc_extradata(avctx, nal, nnal);
+
+ avctx->extradata = p = av_mallocz(s + AV_INPUT_BUFFER_PADDING_SIZE);
+ if (!p)
+ return AVERROR(ENOMEM);
+
+ for (int i = 0; i < nnal; i++) {
+ /* Don't put the SEI in extradata. */
+ if (nal[i].i_type == NAL_SEI) {
+ s = save_sei(avctx, &nal[i]);
+ if (s < 0)
+ return s;
+ continue;
+ }
+ memcpy(p, nal[i].p_payload, nal[i].i_payload);
+ p += nal[i].i_payload;
+ }
+ avctx->extradata_size = p - avctx->extradata;
+
+ return 0;
+}
+
#define PARSE_X264_OPT(name, var)\
if (x4->var && x264_param_parse(&x4->params, name, x4->var) < 0) {\
av_log(avctx, AV_LOG_ERROR, "Error parsing option '%s' with value '%s'.\n", name, x4->var);\
@@ -1233,30 +1368,9 @@ FF_ENABLE_DEPRECATION_WARNINGS
return AVERROR_EXTERNAL;
if (avctx->flags & AV_CODEC_FLAG_GLOBAL_HEADER) {
- x264_nal_t *nal;
- uint8_t *p;
- int nnal, s, i;
-
- s = x264_encoder_headers(x4->enc, &nal, &nnal);
- avctx->extradata = p = av_mallocz(s + AV_INPUT_BUFFER_PADDING_SIZE);
- if (!p)
- return AVERROR(ENOMEM);
-
- for (i = 0; i < nnal; i++) {
- /* Don't put the SEI in extradata. */
- if (nal[i].i_type == NAL_SEI) {
- av_log(avctx, AV_LOG_INFO, "%s\n", nal[i].p_payload+25);
- x4->sei_size = nal[i].i_payload;
- x4->sei = av_malloc(x4->sei_size);
- if (!x4->sei)
- return AVERROR(ENOMEM);
- memcpy(x4->sei, nal[i].p_payload, nal[i].i_payload);
- continue;
- }
- memcpy(p, nal[i].p_payload, nal[i].i_payload);
- p += nal[i].i_payload;
- }
- avctx->extradata_size = p - avctx->extradata;
+ ret = set_extradata(avctx);
+ if (ret < 0)
+ return ret;
}
cpb_props = ff_encode_add_cpb_side_data(avctx);
--
2.25.1
More information about the ffmpeg-devel
mailing list