libavcodec/h264_mp4toannexb_bsf.c - third_party/ffmpeg - Git at Google

 /*
  * H.264 MP4 to Annex B byte stream format filter
  * Copyright (c) 2007 Benoit Fouet <benoit.fouet@free.fr>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 #include <string.h>

 #include "libavutil/intreadwrite.h"
 #include "libavutil/mem.h"

 #include "avcodec.h"
 #include "bsf.h"

 typedef struct H264BSFContext {
     int32_t  sps_offset;
     int32_t  pps_offset;
     uint8_t  length_size;
     uint8_t  new_idr;
     uint8_t  idr_sps_seen;
     uint8_t  idr_pps_seen;
     int      extradata_parsed;
 } H264BSFContext;

 static int alloc_and_copy(AVPacket *out,
                           const uint8_t *sps_pps, uint32_t sps_pps_size,
                           const uint8_t *in, uint32_t in_size)
 {
     uint32_t offset         = out->size;
     uint8_t nal_header_size = offset ? 3 : 4;
     int err;

     err = av_grow_packet(out, sps_pps_size + in_size + nal_header_size);
     if (err < 0)
         return err;

     if (sps_pps)
         memcpy(out->data + offset, sps_pps, sps_pps_size);
     memcpy(out->data + sps_pps_size + nal_header_size + offset, in, in_size);
     if (!offset) {
         AV_WB32(out->data + sps_pps_size, 1);
     } else {
         (out->data + offset + sps_pps_size)[0] =
         (out->data + offset + sps_pps_size)[1] = 0;
         (out->data + offset + sps_pps_size)[2] = 1;
     }

     return 0;
 }

 static int h264_extradata_to_annexb(AVBSFContext *ctx, const int padding)
 {
     H264BSFContext *s = ctx->priv_data;
     uint16_t unit_size;
     uint64_t total_size                 = 0;
     uint8_t *out                        = NULL, unit_nb, sps_done = 0,
              sps_seen                   = 0, pps_seen = 0;
     const uint8_t *extradata            = ctx->par_in->extradata + 4;
     static const uint8_t nalu_header[4] = { 0, 0, 0, 1 };
     int length_size = (*extradata++ & 0x3) + 1; // retrieve length coded size

     s->sps_offset = s->pps_offset = -1;

     /* retrieve sps and pps unit(s) */
     unit_nb = *extradata++ & 0x1f; /* number of sps unit(s) */
     if (!unit_nb) {
         goto pps;
     } else {
         s->sps_offset = 0;
         sps_seen = 1;
     }

     while (unit_nb--) {
         int err;

         unit_size   = AV_RB16(extradata);
         total_size += unit_size + 4;
         if (total_size > INT_MAX - padding) {
             av_log(ctx, AV_LOG_ERROR,
                    "Too big extradata size, corrupted stream or invalid MP4/AVCC bitstream\n");
             av_free(out);
             return AVERROR(EINVAL);
         }
         if (extradata + 2 + unit_size > ctx->par_in->extradata + ctx->par_in->extradata_size) {
             av_log(ctx, AV_LOG_ERROR, "Packet header is not contained in global extradata, "
                    "corrupted stream or invalid MP4/AVCC bitstream\n");
             av_free(out);
             return AVERROR(EINVAL);
         }
         if ((err = av_reallocp(&out, total_size + padding)) < 0)
             return err;
         memcpy(out + total_size - unit_size - 4, nalu_header, 4);
         memcpy(out + total_size - unit_size, extradata + 2, unit_size);
         extradata += 2 + unit_size;
 pps:
         if (!unit_nb && !sps_done++) {
             unit_nb = *extradata++; /* number of pps unit(s) */
             if (unit_nb) {
                 s->pps_offset = total_size;
                 pps_seen = 1;
             }
         }
     }

     if (out)
         memset(out + total_size, 0, padding);

     if (!sps_seen)
         av_log(ctx, AV_LOG_WARNING,
                "Warning: SPS NALU missing or invalid. "
                "The resulting stream may not play.\n");

     if (!pps_seen)
         av_log(ctx, AV_LOG_WARNING,
                "Warning: PPS NALU missing or invalid. "
                "The resulting stream may not play.\n");

     av_freep(&ctx->par_out->extradata);
     ctx->par_out->extradata      = out;
     ctx->par_out->extradata_size = total_size;

     return length_size;
 }

 static int h264_mp4toannexb_init(AVBSFContext *ctx)
 {
     H264BSFContext *s = ctx->priv_data;
     int extra_size = ctx->par_in->extradata_size;
     int ret;

     /* retrieve sps and pps NAL units from extradata */
     if (!extra_size                                               ||
         (extra_size >= 3 && AV_RB24(ctx->par_in->extradata) == 1) ||
         (extra_size >= 4 && AV_RB32(ctx->par_in->extradata) == 1)) {
         av_log(ctx, AV_LOG_VERBOSE,
                "The input looks like it is Annex B already\n");
     } else if (extra_size >= 6) {
         ret = h264_extradata_to_annexb(ctx, AV_INPUT_BUFFER_PADDING_SIZE);
         if (ret < 0)
             return ret;

         s->length_size      = ret;
         s->new_idr          = 1;
         s->idr_sps_seen     = 0;
         s->idr_pps_seen     = 0;
         s->extradata_parsed = 1;
     } else {
         av_log(ctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", extra_size);
         return AVERROR_INVALIDDATA;
     }

     return 0;
 }

 static int h264_mp4toannexb_filter(AVBSFContext *ctx, AVPacket *out)
 {
     H264BSFContext *s = ctx->priv_data;

     AVPacket *in;
     uint8_t unit_type;
     int32_t nal_size;
     uint32_t cumul_size    = 0;
     const uint8_t *buf;
     const uint8_t *buf_end;
     int            buf_size;
     int ret = 0, i;

     ret = ff_bsf_get_packet(ctx, &in);
     if (ret < 0)
         return ret;

     /* nothing to filter */
     if (!s->extradata_parsed) {
         av_packet_move_ref(out, in);
         av_packet_free(&in);
         return 0;
     }

     buf      = in->data;
     buf_size = in->size;
     buf_end  = in->data + in->size;

     do {
         ret= AVERROR(EINVAL);
         if (buf + s->length_size > buf_end)
             goto fail;

         for (nal_size = 0, i = 0; i<s->length_size; i++)
             nal_size = (nal_size << 8) | buf[i];

         buf += s->length_size;
         unit_type = *buf & 0x1f;

         if (nal_size > buf_end - buf || nal_size < 0)
             goto fail;

         if (unit_type == 7)
             s->idr_sps_seen = s->new_idr = 1;
         else if (unit_type == 8) {
             s->idr_pps_seen = s->new_idr = 1;
             /* if SPS has not been seen yet, prepend the AVCC one to PPS */
             if (!s->idr_sps_seen) {
                 if (s->sps_offset == -1)
                     av_log(ctx, AV_LOG_WARNING, "SPS not present in the stream, nor in AVCC, stream may be unreadable\n");
                 else {
                     if ((ret = alloc_and_copy(out,
                                          ctx->par_out->extradata + s->sps_offset,
                                          s->pps_offset != -1 ? s->pps_offset : ctx->par_out->extradata_size - s->sps_offset,
                                          buf, nal_size)) < 0)
                         goto fail;
                     s->idr_sps_seen = 1;
                     goto next_nal;
                 }
             }
         }

         /* if this is a new IDR picture following an IDR picture, reset the idr flag.
          * Just check first_mb_in_slice to be 0 as this is the simplest solution.
          * This could be checking idr_pic_id instead, but would complexify the parsing. */
         if (!s->new_idr && unit_type == 5 && (buf[1] & 0x80))
             s->new_idr = 1;

         /* prepend only to the first type 5 NAL unit of an IDR picture, if no sps/pps are already present */
         if (s->new_idr && unit_type == 5 && !s->idr_sps_seen && !s->idr_pps_seen) {
             if ((ret=alloc_and_copy(out,
                                ctx->par_out->extradata, ctx->par_out->extradata_size,
                                buf, nal_size)) < 0)
                 goto fail;
             s->new_idr = 0;
         /* if only SPS has been seen, also insert PPS */
         } else if (s->new_idr && unit_type == 5 && s->idr_sps_seen && !s->idr_pps_seen) {
             if (s->pps_offset == -1) {
                 av_log(ctx, AV_LOG_WARNING, "PPS not present in the stream, nor in AVCC, stream may be unreadable\n");
                 if ((ret = alloc_and_copy(out, NULL, 0, buf, nal_size)) < 0)
                     goto fail;
             } else if ((ret = alloc_and_copy(out,
                                         ctx->par_out->extradata + s->pps_offset, ctx->par_out->extradata_size - s->pps_offset,
                                         buf, nal_size)) < 0)
                 goto fail;
         } else {
             if ((ret=alloc_and_copy(out, NULL, 0, buf, nal_size)) < 0)
                 goto fail;
             if (!s->new_idr && unit_type == 1) {
                 s->new_idr = 1;
                 s->idr_sps_seen = 0;
                 s->idr_pps_seen = 0;
             }
         }

 next_nal:
         buf        += nal_size;
         cumul_size += nal_size + s->length_size;
     } while (cumul_size < buf_size);

     ret = av_packet_copy_props(out, in);
     if (ret < 0)
         goto fail;

 fail:
     if (ret < 0)
         av_packet_unref(out);
     av_packet_free(&in);

     return ret;
 }

 static const enum AVCodecID codec_ids[] = {
     AV_CODEC_ID_H264, AV_CODEC_ID_NONE,
 };

 const AVBitStreamFilter ff_h264_mp4toannexb_bsf = {
     .name           = "h264_mp4toannexb",
     .priv_data_size = sizeof(H264BSFContext),
     .init           = h264_mp4toannexb_init,
     .filter         = h264_mp4toannexb_filter,
     .codec_ids      = codec_ids,
 };
	/*
	* H.264 MP4 to Annex B byte stream format filter
	* Copyright (c) 2007 Benoit Fouet <benoit.fouet@free.fr>
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* FFmpeg is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include <string.h>

	#include "libavutil/intreadwrite.h"
	#include "libavutil/mem.h"

	#include "avcodec.h"
	#include "bsf.h"

	typedef struct H264BSFContext {
	int32_t sps_offset;
	int32_t pps_offset;
	uint8_t length_size;
	uint8_t new_idr;
	uint8_t idr_sps_seen;
	uint8_t idr_pps_seen;
	int extradata_parsed;
	} H264BSFContext;

	static int alloc_and_copy(AVPacket *out,
	const uint8_t *sps_pps, uint32_t sps_pps_size,
	const uint8_t *in, uint32_t in_size)
	{
	uint32_t offset = out->size;
	uint8_t nal_header_size = offset ? 3 : 4;
	int err;

	err = av_grow_packet(out, sps_pps_size + in_size + nal_header_size);
	if (err < 0)
	return err;

	if (sps_pps)
	memcpy(out->data + offset, sps_pps, sps_pps_size);
	memcpy(out->data + sps_pps_size + nal_header_size + offset, in, in_size);
	if (!offset) {
	AV_WB32(out->data + sps_pps_size, 1);
	} else {
	(out->data + offset + sps_pps_size)[0] =
	(out->data + offset + sps_pps_size)[1] = 0;
	(out->data + offset + sps_pps_size)[2] = 1;
	}

	return 0;
	}

	static int h264_extradata_to_annexb(AVBSFContext *ctx, const int padding)
	{
	H264BSFContext *s = ctx->priv_data;
	uint16_t unit_size;
	uint64_t total_size = 0;
	uint8_t *out = NULL, unit_nb, sps_done = 0,
	sps_seen = 0, pps_seen = 0;
	const uint8_t *extradata = ctx->par_in->extradata + 4;
	static const uint8_t nalu_header[4] = { 0, 0, 0, 1 };
	int length_size = (*extradata++ & 0x3) + 1; // retrieve length coded size

	s->sps_offset = s->pps_offset = -1;

	/* retrieve sps and pps unit(s) */
	unit_nb = extradata++ & 0x1f; / number of sps unit(s) */
	if (!unit_nb) {
	goto pps;
	} else {
	s->sps_offset = 0;
	sps_seen = 1;
	}

	while (unit_nb--) {
	int err;

	unit_size = AV_RB16(extradata);
	total_size += unit_size + 4;
	if (total_size > INT_MAX - padding) {
	av_log(ctx, AV_LOG_ERROR,
	"Too big extradata size, corrupted stream or invalid MP4/AVCC bitstream\n");
	av_free(out);
	return AVERROR(EINVAL);
	}
	if (extradata + 2 + unit_size > ctx->par_in->extradata + ctx->par_in->extradata_size) {
	av_log(ctx, AV_LOG_ERROR, "Packet header is not contained in global extradata, "
	"corrupted stream or invalid MP4/AVCC bitstream\n");
	av_free(out);
	return AVERROR(EINVAL);
	}
	if ((err = av_reallocp(&out, total_size + padding)) < 0)
	return err;
	memcpy(out + total_size - unit_size - 4, nalu_header, 4);
	memcpy(out + total_size - unit_size, extradata + 2, unit_size);
	extradata += 2 + unit_size;
	pps:
	if (!unit_nb && !sps_done++) {
	unit_nb = extradata++; / number of pps unit(s) */
	if (unit_nb) {
	s->pps_offset = total_size;
	pps_seen = 1;
	}
	}
	}

	if (out)
	memset(out + total_size, 0, padding);

	if (!sps_seen)
	av_log(ctx, AV_LOG_WARNING,
	"Warning: SPS NALU missing or invalid. "
	"The resulting stream may not play.\n");

	if (!pps_seen)
	av_log(ctx, AV_LOG_WARNING,
	"Warning: PPS NALU missing or invalid. "
	"The resulting stream may not play.\n");

	av_freep(&ctx->par_out->extradata);
	ctx->par_out->extradata = out;
	ctx->par_out->extradata_size = total_size;

	return length_size;
	}

	static int h264_mp4toannexb_init(AVBSFContext *ctx)
	{
	H264BSFContext *s = ctx->priv_data;
	int extra_size = ctx->par_in->extradata_size;
	int ret;

	/* retrieve sps and pps NAL units from extradata */
	if (!extra_size \|\|
	(extra_size >= 3 && AV_RB24(ctx->par_in->extradata) == 1) \|\|
	(extra_size >= 4 && AV_RB32(ctx->par_in->extradata) == 1)) {
	av_log(ctx, AV_LOG_VERBOSE,
	"The input looks like it is Annex B already\n");
	} else if (extra_size >= 6) {
	ret = h264_extradata_to_annexb(ctx, AV_INPUT_BUFFER_PADDING_SIZE);
	if (ret < 0)
	return ret;

	s->length_size = ret;
	s->new_idr = 1;
	s->idr_sps_seen = 0;
	s->idr_pps_seen = 0;
	s->extradata_parsed = 1;
	} else {
	av_log(ctx, AV_LOG_ERROR, "Invalid extradata size: %d\n", extra_size);
	return AVERROR_INVALIDDATA;
	}

	return 0;
	}

	static int h264_mp4toannexb_filter(AVBSFContext ctx, AVPacket out)
	{
	H264BSFContext *s = ctx->priv_data;

	AVPacket *in;
	uint8_t unit_type;
	int32_t nal_size;
	uint32_t cumul_size = 0;
	const uint8_t *buf;
	const uint8_t *buf_end;
	int buf_size;
	int ret = 0, i;

	ret = ff_bsf_get_packet(ctx, &in);
	if (ret < 0)
	return ret;

	/* nothing to filter */
	if (!s->extradata_parsed) {
	av_packet_move_ref(out, in);
	av_packet_free(&in);
	return 0;
	}

	buf = in->data;
	buf_size = in->size;
	buf_end = in->data + in->size;

	do {
	ret= AVERROR(EINVAL);
	if (buf + s->length_size > buf_end)
	goto fail;

	for (nal_size = 0, i = 0; i<s->length_size; i++)
	nal_size = (nal_size << 8) \| buf[i];

	buf += s->length_size;
	unit_type = *buf & 0x1f;

	if (nal_size > buf_end - buf \|\| nal_size < 0)
	goto fail;

	if (unit_type == 7)
	s->idr_sps_seen = s->new_idr = 1;
	else if (unit_type == 8) {
	s->idr_pps_seen = s->new_idr = 1;
	/* if SPS has not been seen yet, prepend the AVCC one to PPS */
	if (!s->idr_sps_seen) {
	if (s->sps_offset == -1)
	av_log(ctx, AV_LOG_WARNING, "SPS not present in the stream, nor in AVCC, stream may be unreadable\n");
	else {
	if ((ret = alloc_and_copy(out,
	ctx->par_out->extradata + s->sps_offset,
	s->pps_offset != -1 ? s->pps_offset : ctx->par_out->extradata_size - s->sps_offset,
	buf, nal_size)) < 0)
	goto fail;
	s->idr_sps_seen = 1;
	goto next_nal;
	}
	}
	}

	/* if this is a new IDR picture following an IDR picture, reset the idr flag.
	* Just check first_mb_in_slice to be 0 as this is the simplest solution.
	* This could be checking idr_pic_id instead, but would complexify the parsing. */
	if (!s->new_idr && unit_type == 5 && (buf[1] & 0x80))
	s->new_idr = 1;

	/* prepend only to the first type 5 NAL unit of an IDR picture, if no sps/pps are already present */
	if (s->new_idr && unit_type == 5 && !s->idr_sps_seen && !s->idr_pps_seen) {
	if ((ret=alloc_and_copy(out,
	ctx->par_out->extradata, ctx->par_out->extradata_size,
	buf, nal_size)) < 0)
	goto fail;
	s->new_idr = 0;
	/* if only SPS has been seen, also insert PPS */
	} else if (s->new_idr && unit_type == 5 && s->idr_sps_seen && !s->idr_pps_seen) {
	if (s->pps_offset == -1) {
	av_log(ctx, AV_LOG_WARNING, "PPS not present in the stream, nor in AVCC, stream may be unreadable\n");
	if ((ret = alloc_and_copy(out, NULL, 0, buf, nal_size)) < 0)
	goto fail;
	} else if ((ret = alloc_and_copy(out,
	ctx->par_out->extradata + s->pps_offset, ctx->par_out->extradata_size - s->pps_offset,
	buf, nal_size)) < 0)
	goto fail;
	} else {
	if ((ret=alloc_and_copy(out, NULL, 0, buf, nal_size)) < 0)
	goto fail;
	if (!s->new_idr && unit_type == 1) {
	s->new_idr = 1;
	s->idr_sps_seen = 0;
	s->idr_pps_seen = 0;
	}
	}

	next_nal:
	buf += nal_size;
	cumul_size += nal_size + s->length_size;
	} while (cumul_size < buf_size);

	ret = av_packet_copy_props(out, in);
	if (ret < 0)
	goto fail;

	fail:
	if (ret < 0)
	av_packet_unref(out);
	av_packet_free(&in);

	return ret;
	}

	static const enum AVCodecID codec_ids[] = {
	AV_CODEC_ID_H264, AV_CODEC_ID_NONE,
	};

	const AVBitStreamFilter ff_h264_mp4toannexb_bsf = {
	.name = "h264_mp4toannexb",
	.priv_data_size = sizeof(H264BSFContext),
	.init = h264_mp4toannexb_init,
	.filter = h264_mp4toannexb_filter,
	.codec_ids = codec_ids,
	};