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authorAndreas Huber <andih@google.com>2010-10-08 12:06:27 -0700
committerAndreas Huber <andih@google.com>2010-10-08 12:06:27 -0700
commitc68a48c474f609df3eeb7d9738675d6ac8835e0a (patch)
tree4513bc3b15dc583bbca45db9c67f4d0aba8b1172 /media/libstagefright/avc_utils.cpp
parent6f3cba53efdd985ab13734c7ad90eb373ae9b9f7 (diff)
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Refactor some more h.264 utility code out into avc_utils. Work around a hardware decoder issue by making sure the first access unit submitted to a decoder at startup or after seek is an IDR.
Change-Id: I61936601e55df7e4c23a8c13087579a4f85bd6e6
Diffstat (limited to 'media/libstagefright/avc_utils.cpp')
-rw-r--r--media/libstagefright/avc_utils.cpp174
1 files changed, 174 insertions, 0 deletions
diff --git a/media/libstagefright/avc_utils.cpp b/media/libstagefright/avc_utils.cpp
index 8762d29..478e40c 100644
--- a/media/libstagefright/avc_utils.cpp
+++ b/media/libstagefright/avc_utils.cpp
@@ -18,6 +18,9 @@
#include <media/stagefright/foundation/ABitReader.h>
#include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/MediaDefs.h>
+#include <media/stagefright/MediaErrors.h>
+#include <media/stagefright/MetaData.h>
namespace android {
@@ -124,5 +127,176 @@ void FindAVCDimensions(
}
}
+status_t getNextNALUnit(
+ const uint8_t **_data, size_t *_size,
+ const uint8_t **nalStart, size_t *nalSize,
+ bool startCodeFollows) {
+ const uint8_t *data = *_data;
+ size_t size = *_size;
+
+ *nalStart = NULL;
+ *nalSize = 0;
+
+ if (size == 0) {
+ return -EAGAIN;
+ }
+
+ // Skip any number of leading 0x00.
+
+ size_t offset = 0;
+ while (offset < size && data[offset] == 0x00) {
+ ++offset;
+ }
+
+ if (offset == size) {
+ return -EAGAIN;
+ }
+
+ // A valid startcode consists of at least two 0x00 bytes followed by 0x01.
+
+ if (offset < 2 || data[offset] != 0x01) {
+ return ERROR_MALFORMED;
+ }
+
+ ++offset;
+
+ size_t startOffset = offset;
+
+ for (;;) {
+ while (offset < size && data[offset] != 0x01) {
+ ++offset;
+ }
+
+ if (offset == size) {
+ if (startCodeFollows) {
+ offset = size + 2;
+ break;
+ }
+
+ return -EAGAIN;
+ }
+
+ if (data[offset - 1] == 0x00 && data[offset - 2] == 0x00) {
+ break;
+ }
+
+ ++offset;
+ }
+
+ size_t endOffset = offset - 2;
+ while (data[endOffset - 1] == 0x00) {
+ --endOffset;
+ }
+
+ *nalStart = &data[startOffset];
+ *nalSize = endOffset - startOffset;
+
+ if (offset + 2 < size) {
+ *_data = &data[offset - 2];
+ *_size = size - offset + 2;
+ } else {
+ *_data = NULL;
+ *_size = 0;
+ }
+
+ return OK;
+}
+
+static sp<ABuffer> FindNAL(
+ const uint8_t *data, size_t size, unsigned nalType,
+ size_t *stopOffset) {
+ const uint8_t *nalStart;
+ size_t nalSize;
+ while (getNextNALUnit(&data, &size, &nalStart, &nalSize, true) == OK) {
+ if ((nalStart[0] & 0x1f) == nalType) {
+ sp<ABuffer> buffer = new ABuffer(nalSize);
+ memcpy(buffer->data(), nalStart, nalSize);
+ return buffer;
+ }
+ }
+
+ return NULL;
+}
+
+sp<MetaData> MakeAVCCodecSpecificData(const sp<ABuffer> &accessUnit) {
+ const uint8_t *data = accessUnit->data();
+ size_t size = accessUnit->size();
+
+ sp<ABuffer> seqParamSet = FindNAL(data, size, 7, NULL);
+ if (seqParamSet == NULL) {
+ return NULL;
+ }
+
+ int32_t width, height;
+ FindAVCDimensions(seqParamSet, &width, &height);
+
+ size_t stopOffset;
+ sp<ABuffer> picParamSet = FindNAL(data, size, 8, &stopOffset);
+ CHECK(picParamSet != NULL);
+
+ size_t csdSize =
+ 1 + 3 + 1 + 1
+ + 2 * 1 + seqParamSet->size()
+ + 1 + 2 * 1 + picParamSet->size();
+
+ sp<ABuffer> csd = new ABuffer(csdSize);
+ uint8_t *out = csd->data();
+
+ *out++ = 0x01; // configurationVersion
+ memcpy(out, seqParamSet->data() + 1, 3); // profile/level...
+ out += 3;
+ *out++ = (0x3f << 2) | 1; // lengthSize == 2 bytes
+ *out++ = 0xe0 | 1;
+
+ *out++ = seqParamSet->size() >> 8;
+ *out++ = seqParamSet->size() & 0xff;
+ memcpy(out, seqParamSet->data(), seqParamSet->size());
+ out += seqParamSet->size();
+
+ *out++ = 1;
+
+ *out++ = picParamSet->size() >> 8;
+ *out++ = picParamSet->size() & 0xff;
+ memcpy(out, picParamSet->data(), picParamSet->size());
+
+#if 0
+ LOGI("AVC seq param set");
+ hexdump(seqParamSet->data(), seqParamSet->size());
+#endif
+
+ sp<MetaData> meta = new MetaData;
+ meta->setCString(kKeyMIMEType, MEDIA_MIMETYPE_VIDEO_AVC);
+
+ meta->setData(kKeyAVCC, 0, csd->data(), csd->size());
+ meta->setInt32(kKeyWidth, width);
+ meta->setInt32(kKeyHeight, height);
+
+ LOGI("found AVC codec config (%d x %d)", width, height);
+
+ return meta;
+}
+
+bool IsIDR(const sp<ABuffer> &buffer) {
+ const uint8_t *data = buffer->data();
+ size_t size = buffer->size();
+
+ bool foundIDR = false;
+
+ const uint8_t *nalStart;
+ size_t nalSize;
+ while (getNextNALUnit(&data, &size, &nalStart, &nalSize, true) == OK) {
+ CHECK_GT(nalSize, 0u);
+
+ unsigned nalType = nalStart[0] & 0x1f;
+
+ if (nalType == 5) {
+ foundIDR = true;
+ break;
+ }
+ }
+
+ return foundIDR;
+}
+
} // namespace android