steve
/
winamp
mirror of https://github.com/WinampDesktop/winamp.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
winamp/Src/mpeg4dec/mp4stream.c

327 lines
8.8 KiB
C
Raw Blame History

/* ///////////////////////////////////////////////////////////////////////
//
// INTEL CORPORATION PROPRIETARY INFORMATION
// This software is supplied under the terms of a license agreement or
// nondisclosure agreement with Intel Corporation and may not be copied
// or disclosed except in accordance with the terms of that agreement.
// Copyright (c) 2001-2008 Intel Corporation. All Rights Reserved.
//
// Description: Decodes MPEG-4 bitstream.
//
*/
#include "mp4def.h"
#ifndef USE_INLINE_BITS_FUNC
uint32_t mp4_ShowBits(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bufptr;
uint32_t tmp = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | (ptr[3]);
tmp <<= pInfo->bitoff;
tmp >>= 32 - n;
return tmp;
}
uint32_t mp4_ShowBit(mp4_Info* pInfo)
{
uint32_t tmp = pInfo->bufptr[0];
tmp >>= 7 - pInfo->bitoff;
return (tmp & 1);
}
uint32_t mp4_ShowBits9(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bufptr;
uint32_t tmp = (ptr[0] << 8) | ptr[1];
tmp <<= (pInfo->bitoff + 16);
tmp >>= 32 - n;
return tmp;
}
void mp4_FlushBits(mp4_Info* pInfo, int32_t n)
{
n = n + pInfo->bitoff;
pInfo->bufptr += n >> 3;
pInfo->bitoff = n & 7;
}
uint32_t mp4_GetBits(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bufptr;
uint32_t tmp = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | (ptr[3]);
tmp <<= pInfo->bitoff;
tmp >>= 32 - n;
n = n + pInfo->bitoff;
pInfo->bufptr += n >> 3;
pInfo->bitoff = n & 7;
return tmp;
}
uint32_t mp4_GetBits9(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bufptr;
uint32_t tmp = (ptr[0] << 8) | ptr[1];
tmp <<= (pInfo->bitoff + 16);
tmp >>= 32 - n;
n = n + pInfo->bitoff;
pInfo->bufptr += n >> 3;
pInfo->bitoff = n & 7;
return tmp;
}
void mp4_AlignBits(mp4_Info* pInfo)
{
if (pInfo->bitoff > 0) {
pInfo->bitoff = 0;
(pInfo->bufptr)++;
}
}
void mp4_AlignBits7F(mp4_Info* pInfo)
{
if (pInfo->bitoff > 0) {
pInfo->bitoff = 0;
(pInfo->bufptr)++;
} else {
if (*pInfo->bufptr == 0x7F)
(pInfo->bufptr)++;
}
}
uint32_t mp4_ShowBitsAlign(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bitoff ? (pInfo->bufptr + 1) : pInfo->bufptr;
uint32_t tmp = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | (ptr[3]);
tmp >>= 32 - n;
return tmp;
}
uint32_t mp4_ShowBitsAlign7F(mp4_Info* pInfo, int32_t n)
{
uint8_t* ptr = pInfo->bitoff ? (pInfo->bufptr + 1) : pInfo->bufptr;
uint32_t tmp;
if (!pInfo->bitoff) {
if (*ptr == 0x7F)
ptr ++;
}
tmp = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | (ptr[3]);
tmp >>= 32 - n;
return tmp;
}
#endif
uint8_t* mp4_FindStartCodePtr(mp4_Info* pInfo)
{
int32_t i, len = pInfo->buflen - (pInfo->bufptr - pInfo->buffer);
uint8_t* ptr = pInfo->bufptr;
for (i = 0; i < len - 3; i++) {
if (ptr[i] == 0 && ptr[i + 1] == 0 && ptr[i + 2] == 1) {
return ptr + i + 3;
}
}
return NULL;
}
uint8_t* mp4_FindStartCodeOrShortPtr(mp4_Info* pInfo)
{
int32_t i, len = pInfo->buflen - (pInfo->bufptr - pInfo->buffer);
uint8_t* ptr = pInfo->bufptr;
for (i = 0; i < len - 3; i++) {
if (ptr[i] == 0 && ptr[i + 1] == 0 && ptr[i + 2] == 1) {
return ptr + i + 3;
}
// short_video_header
if (ptr[i] == 0 && ptr[i + 1] == 0 && (ptr[i + 2] & 0xFC) == 0x80) {
return ptr + i;
}
}
return NULL;
}
int32_t mp4_SeekStartCodePtr(mp4_Info* pInfo)
{
uint8_t* ptr;
if (pInfo->bitoff) {
pInfo->bufptr ++;
pInfo->bitoff = 0;
}
ptr = mp4_FindStartCodePtr(pInfo);
if (ptr) {
pInfo->bufptr = ptr;
return 1;
} else {
pInfo->bufptr = pInfo->buffer + (pInfo->buflen > 3 ? pInfo->buflen - 3 : 0);
return 0;
}
}
int32_t mp4_SeekStartCodeOrShortPtr(mp4_Info* pInfo)
{
uint8_t* ptr;
if (pInfo->bitoff) {
pInfo->bufptr ++;
pInfo->bitoff = 0;
}
ptr = mp4_FindStartCodeOrShortPtr(pInfo);
if (ptr) {
pInfo->bufptr = ptr;
return 1;
} else {
pInfo->bufptr = pInfo->buffer + (pInfo->buflen > 3 ? pInfo->buflen - 3 : 0);
return 0;
}
}
int32_t mp4_SeekStartCodeValue(mp4_Info* pInfo, uint8_t code)
{
while (mp4_SeekStartCodePtr(pInfo)) {
if (*(pInfo->bufptr) == code) {
(pInfo->bufptr) ++;
return 1;
}
}
return 0;
}
uint8_t* mp4_FindShortVideoStartMarkerPtr(mp4_Info* pInfo)
{
int32_t i, len = pInfo->buflen - (pInfo->bufptr - pInfo->buffer);
uint8_t* ptr = pInfo->bufptr;
for (i = 0; i < len - 3; i++) {
if (ptr[i] == 0 && ptr[i + 1] == 0 && (ptr[i + 2] & (~3)) == 0x80) {
return ptr + i + 2;
}
}
return NULL;
}
int32_t mp4_SeekShortVideoStartMarker(mp4_Info* pInfo)
{
uint8_t* ptr;
if (pInfo->bitoff) {
pInfo->bufptr ++;
pInfo->bitoff = 0;
}
ptr = mp4_FindShortVideoStartMarkerPtr(pInfo);
if (ptr) {
pInfo->bufptr = ptr;
return 1;
} else {
pInfo->bufptr = pInfo->buffer + (pInfo->buflen > 3 ? pInfo->buflen - 3 : 0);
return 0;
}
}
//changed pInfo->len on pInfo->buflen!!!
int32_t mp4_SeekGOBMarker(mp4_Info* pInfo)
{
for (; pInfo->bufptr < pInfo->buffer + pInfo->buflen - 2; pInfo->bufptr ++) {
if (pInfo->bufptr[0] == 0) {
pInfo->bitoff = 0;
if (pInfo->bufptr[0] == 0 && pInfo->bufptr[1] == 0 && (pInfo->bufptr[2] & (~3)) == 0x80)
return 0;
pInfo->bufptr --;
for (pInfo->bitoff = 1; pInfo->bitoff <= 7; pInfo->bitoff ++) {
if (mp4_ShowBits(pInfo, 17) == 1)
return 1;
}
pInfo->bufptr ++;
for (pInfo->bitoff = 0; pInfo->bitoff <= 7; pInfo->bitoff ++) {
if (mp4_ShowBits(pInfo, 17) == 1)
return 1;
}
pInfo->bufptr ++;
}
}
return 0;
}
int32_t mp4_SeekResyncMarker(mp4_Info* pInfo)
{
int32_t rml;
if (pInfo->VisualObject.VideoObject.VideoObjectPlane.coding_type == MP4_VOP_TYPE_I)
rml = 17;
else if (pInfo->VisualObject.VideoObject.VideoObjectPlane.coding_type == MP4_VOP_TYPE_B)
rml = 16 + IPP_MAX(pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_forward, pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_backward);
else
rml = 16 + pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_forward;
pInfo->bitoff = 0;
for (; pInfo->bufptr < pInfo->buffer + pInfo->buflen - 2; pInfo->bufptr ++) {
if (pInfo->bufptr[0] == 0) {
if (pInfo->bufptr[0] == 0 && pInfo->bufptr[1] == 0 && pInfo->bufptr[2] == 1)
return 0;
if (mp4_ShowBits(pInfo, rml) == 1) {
// check stuffing bits
pInfo->bufptr --;
pInfo->bitoff = 7;
while (pInfo->bitoff > 0 && mp4_ShowBit(pInfo))
pInfo->bitoff --;
if (pInfo->bitoff == 0 && mp4_ShowBit(pInfo)) {
// stuffing bits are invalid
pInfo->bufptr[0] = 0x7f;
}
return 1;
}
pInfo->bufptr += 2;
}
}
return 0;
}
int32_t mp4_FindResyncMarker(mp4_Info* pInfo)
{
int32_t rml;
if (pInfo->VisualObject.VideoObject.VideoObjectPlane.coding_type == MP4_VOP_TYPE_I)
rml = 17;
else if (pInfo->VisualObject.VideoObject.VideoObjectPlane.coding_type == MP4_VOP_TYPE_B)
rml = 16 + IPP_MAX(pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_forward, pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_backward);
else
rml = 16 + pInfo->VisualObject.VideoObject.VideoObjectPlane.fcode_forward;
pInfo->bitoff = 0;
for (; pInfo->bufptr < pInfo->buffer + pInfo->buflen - 2; pInfo->bufptr ++) {
if (pInfo->bufptr[0] == 0)
{
if (pInfo->bufptr[0] == 0 && pInfo->bufptr[1] == 0 && pInfo->bufptr[2] == 1)
return 0;
if (mp4_ShowBits(pInfo, rml) == 1)
{
return rml;
}
}
}
return 0;
}
int mp4_IsStartCodeOrShort(mp4_Info* pInfo)
{
if (pInfo->bufptr[0] == 0 && pInfo->bufptr[1] == 0 && (pInfo->bufptr[2] == 1 || ((pInfo->bufptr[2] & 0xFC) == 0x80)))
return 1;
return 0;
}
int mp4_IsStartCodeValue(mp4_Info* pInfo, int min, int max)
{
if (pInfo->bufptr[0-3] == 0 && pInfo->bufptr[1-3] == 0 && pInfo->bufptr[2-3] == 1)
if (pInfo->bufptr[3-3] >= min && pInfo->bufptr[3-3] <= max)
return 1;
return 0;
}
int mp4_IsShortCode(mp4_Info* pInfo)
{
if (pInfo->bufptr[0] == 0 && pInfo->bufptr[1] == 0 && ((pInfo->bufptr[2] & 0xFC) == 0x80))
return 1;
return 0;
}
Reference in New Issue View Git Blame Copy Permalink