PeerStreamer

/*

 * Dirac encoder support via Schroedinger libraries

 * Copyright (c) 2008 BBC, Anuradha Suraparaju <asuraparaju at gmail dot com >

 *

 * 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

 */

/**

* @file

* Dirac encoder support via libschroedinger-1.0 libraries. More details about

* the Schroedinger project can be found at http://www.diracvideo.org/.

* The library implements Dirac Specification Version 2.2

* (http://dirac.sourceforge.net/specification.html).

*/

#undef NDEBUG

#include <assert.h>

#include <schroedinger/schro.h>

#include <schroedinger/schrodebug.h>

#include <schroedinger/schrovideoformat.h>

#include "avcodec.h"

#include "libdirac_libschro.h"

#include "libschroedinger.h"

#include "bytestream.h"

/** libschroedinger encoder private data */

typedef struct FfmpegSchroEncoderParams {

    /** Schroedinger video format */

    SchroVideoFormat *format;

    /** Schroedinger frame format */

    SchroFrameFormat frame_format;

    /** frame being encoded */

    AVFrame picture;

    /** frame size */

    int frame_size;

    /** Schroedinger encoder handle*/

    SchroEncoder* encoder;

    /** buffer to store encoder output before writing it to the frame queue*/

    unsigned char *enc_buf;

    /** Size of encoder buffer*/

    int enc_buf_size;

    /** queue storing encoded frames */

    FfmpegDiracSchroQueue enc_frame_queue;

    /** end of sequence signalled */

    int eos_signalled;

    /** end of sequence pulled */

    int eos_pulled;

} FfmpegSchroEncoderParams;

/**

* Works out Schro-compatible chroma format.

*/

static int SetSchroChromaFormat(AVCodecContext *avccontext)

{

    int num_formats = sizeof(ffmpeg_schro_pixel_format_map) /

                      sizeof(ffmpeg_schro_pixel_format_map[0]);

    int idx;

    FfmpegSchroEncoderParams* p_schro_params = avccontext->priv_data;

    for (idx = 0; idx < num_formats; ++idx) {

        if (ffmpeg_schro_pixel_format_map[idx].ff_pix_fmt ==

            avccontext->pix_fmt) {

            p_schro_params->format->chroma_format =

                            ffmpeg_schro_pixel_format_map[idx].schro_pix_fmt;

            return 0;

        }

    }

    av_log(avccontext, AV_LOG_ERROR,

           "This codec currently only supports planar YUV 4:2:0, 4:2:2"

           " and 4:4:4 formats.\n");

    return -1;

}

static int libschroedinger_encode_init(AVCodecContext *avccontext)

{

    FfmpegSchroEncoderParams* p_schro_params = avccontext->priv_data;

    SchroVideoFormatEnum preset;

    /* Initialize the libraries that libschroedinger depends on. */

    schro_init();

    /* Create an encoder object. */

    p_schro_params->encoder = schro_encoder_new();

    if (!p_schro_params->encoder) {

        av_log(avccontext, AV_LOG_ERROR,

               "Unrecoverable Error: schro_encoder_new failed. ");

        return -1;

    }

    /* Initialize the format. */

    preset = ff_get_schro_video_format_preset(avccontext);

    p_schro_params->format =

                    schro_encoder_get_video_format(p_schro_params->encoder);

    schro_video_format_set_std_video_format(p_schro_params->format, preset);

    p_schro_params->format->width  = avccontext->width;

    p_schro_params->format->height = avccontext->height;

    if (SetSchroChromaFormat(avccontext) == -1)

        return -1;

    if (avccontext->color_primaries == AVCOL_PRI_BT709) {

        p_schro_params->format->colour_primaries = SCHRO_COLOUR_PRIMARY_HDTV;

    } else if (avccontext->color_primaries == AVCOL_PRI_BT470BG) {

        p_schro_params->format->colour_primaries = SCHRO_COLOUR_PRIMARY_SDTV_625;

    } else if (avccontext->color_primaries == AVCOL_PRI_SMPTE170M) {

        p_schro_params->format->colour_primaries = SCHRO_COLOUR_PRIMARY_SDTV_525;

    }

    if (avccontext->colorspace == AVCOL_SPC_BT709) {

        p_schro_params->format->colour_matrix = SCHRO_COLOUR_MATRIX_HDTV;

    } else if (avccontext->colorspace == AVCOL_SPC_BT470BG) {

        p_schro_params->format->colour_matrix = SCHRO_COLOUR_MATRIX_SDTV;

    }

    if (avccontext->color_trc == AVCOL_TRC_BT709) {

        p_schro_params->format->transfer_function = SCHRO_TRANSFER_CHAR_TV_GAMMA;

    }

    if (ff_get_schro_frame_format(p_schro_params->format->chroma_format,

                                  &p_schro_params->frame_format) == -1) {

        av_log(avccontext, AV_LOG_ERROR,

               "This codec currently supports only planar YUV 4:2:0, 4:2:2"

               " and 4:4:4 formats.\n");

        return -1;

    }

    p_schro_params->format->frame_rate_numerator   = avccontext->time_base.den;

    p_schro_params->format->frame_rate_denominator = avccontext->time_base.num;

    p_schro_params->frame_size = avpicture_get_size(avccontext->pix_fmt,

                                                    avccontext->width,

                                                    avccontext->height);

    avccontext->coded_frame = &p_schro_params->picture;

    if (!avccontext->gop_size) {

        schro_encoder_setting_set_double(p_schro_params->encoder,

                                         "gop_structure",

                                         SCHRO_ENCODER_GOP_INTRA_ONLY);

        if (avccontext->coder_type == FF_CODER_TYPE_VLC)

            schro_encoder_setting_set_double(p_schro_params->encoder,

                                             "enable_noarith", 1);

    } else {

        schro_encoder_setting_set_double(p_schro_params->encoder,

                                         "au_distance", avccontext->gop_size);

        avccontext->has_b_frames = 1;

    }

    /* FIXME - Need to handle SCHRO_ENCODER_RATE_CONTROL_LOW_DELAY. */

    if (avccontext->flags & CODEC_FLAG_QSCALE) {

        if (!avccontext->global_quality) {

            /* lossless coding */

            schro_encoder_setting_set_double(p_schro_params->encoder,

                                             "rate_control",

                                             SCHRO_ENCODER_RATE_CONTROL_LOSSLESS);

        } else {

            int quality;

            schro_encoder_setting_set_double(p_schro_params->encoder,

                                             "rate_control",

                                             SCHRO_ENCODER_RATE_CONTROL_CONSTANT_QUALITY);

            quality = avccontext->global_quality / FF_QP2LAMBDA;

            if (quality > 10)

                quality = 10;

            schro_encoder_setting_set_double(p_schro_params->encoder,

                                             "quality", quality);

        }

    } else {

        schro_encoder_setting_set_double(p_schro_params->encoder,

                                         "rate_control",

                                         SCHRO_ENCODER_RATE_CONTROL_CONSTANT_BITRATE);

        schro_encoder_setting_set_double(p_schro_params->encoder,

                                         "bitrate",

                                         avccontext->bit_rate);

    }

    if (avccontext->flags & CODEC_FLAG_INTERLACED_ME)

        /* All material can be coded as interlaced or progressive

           irrespective of the type of source material. */

        schro_encoder_setting_set_double(p_schro_params->encoder,

                                         "interlaced_coding", 1);

    schro_encoder_setting_set_double(p_schro_params->encoder, "open_gop",

                                     !(avccontext->flags & CODEC_FLAG_CLOSED_GOP));

    /* FIXME: Signal range hardcoded to 8-bit data until both libschroedinger

     * and libdirac support other bit-depth data. */

    schro_video_format_set_std_signal_range(p_schro_params->format,

                                            SCHRO_SIGNAL_RANGE_8BIT_VIDEO);

    /* Set the encoder format. */

    schro_encoder_set_video_format(p_schro_params->encoder,

                                   p_schro_params->format);

    /* Set the debug level. */

    schro_debug_set_level(avccontext->debug);

    schro_encoder_start(p_schro_params->encoder);

    /* Initialize the encoded frame queue. */

    ff_dirac_schro_queue_init(&p_schro_params->enc_frame_queue);

    return 0;

}

static SchroFrame *libschroedinger_frame_from_data(AVCodecContext *avccontext,

                                                   void *in_data)

{

    FfmpegSchroEncoderParams* p_schro_params = avccontext->priv_data;

    SchroFrame *in_frame;

    /* Input line size may differ from what the codec supports. Especially

     * when transcoding from one format to another. So use avpicture_layout

     * to copy the frame. */

    in_frame = ff_create_schro_frame(avccontext, p_schro_params->frame_format);

    if (in_frame)

        avpicture_layout((AVPicture *)in_data, avccontext->pix_fmt,

                          avccontext->width, avccontext->height,

                          in_frame->components[0].data,

                          p_schro_params->frame_size);

    return in_frame;

}

static void SchroedingerFreeFrame(void *data)

{

    FfmpegDiracSchroEncodedFrame *enc_frame = data;

    av_freep(&(enc_frame->p_encbuf));

    av_free(enc_frame);

}

static int libschroedinger_encode_frame(AVCodecContext *avccontext,

                                        unsigned char *frame,

                                        int buf_size, void *data)

{

    int enc_size = 0;

    FfmpegSchroEncoderParams* p_schro_params = avccontext->priv_data;

    SchroEncoder *encoder = p_schro_params->encoder;

    struct FfmpegDiracSchroEncodedFrame* p_frame_output = NULL;

    int go = 1;

    SchroBuffer *enc_buf;

    int presentation_frame;

    int parse_code;

    int last_frame_in_sequence = 0;

    if (!data) {

        /* Push end of sequence if not already signalled. */

        if (!p_schro_params->eos_signalled) {

            schro_encoder_end_of_stream(encoder);

            p_schro_params->eos_signalled = 1;

        }

    } else {

        /* Allocate frame data to schro input buffer. */

        SchroFrame *in_frame = libschroedinger_frame_from_data(avccontext,

                                                               data);

        /* Load next frame. */

        schro_encoder_push_frame(encoder, in_frame);

    }

    if (p_schro_params->eos_pulled)

        go = 0;

    /* Now check to see if we have any output from the encoder. */

    while (go) {

        SchroStateEnum state;

        state = schro_encoder_wait(encoder);

        switch (state) {

        case SCHRO_STATE_HAVE_BUFFER:

        case SCHRO_STATE_END_OF_STREAM:

            enc_buf = schro_encoder_pull(encoder, &presentation_frame);

            assert(enc_buf->length > 0);

            assert(enc_buf->length <= buf_size);

            parse_code = enc_buf->data[4];

            /* All non-frame data is prepended to actual frame data to

             * be able to set the pts correctly. So we don't write data

             * to the frame output queue until we actually have a frame

             */

            p_schro_params->enc_buf = av_realloc(p_schro_params->enc_buf,

                                                 p_schro_params->enc_buf_size + enc_buf->length);

            memcpy(p_schro_params->enc_buf + p_schro_params->enc_buf_size,

                   enc_buf->data, enc_buf->length);

            p_schro_params->enc_buf_size += enc_buf->length;

            if (state == SCHRO_STATE_END_OF_STREAM) {

                p_schro_params->eos_pulled = 1;

                go = 0;

            }

            if (!SCHRO_PARSE_CODE_IS_PICTURE(parse_code)) {

                schro_buffer_unref(enc_buf);

                break;

            }

            /* Create output frame. */

            p_frame_output = av_mallocz(sizeof(FfmpegDiracSchroEncodedFrame));

            /* Set output data. */

            p_frame_output->size     = p_schro_params->enc_buf_size;

            p_frame_output->p_encbuf = p_schro_params->enc_buf;

            if (SCHRO_PARSE_CODE_IS_INTRA(parse_code) &&

                SCHRO_PARSE_CODE_IS_REFERENCE(parse_code))

                p_frame_output->key_frame = 1;

            /* Parse the coded frame number from the bitstream. Bytes 14

             * through 17 represesent the frame number. */

            p_frame_output->frame_num = AV_RB32(enc_buf->data + 13);

            ff_dirac_schro_queue_push_back(&p_schro_params->enc_frame_queue,

                                           p_frame_output);

            p_schro_params->enc_buf_size = 0;

            p_schro_params->enc_buf      = NULL;

            schro_buffer_unref(enc_buf);

            break;

        case SCHRO_STATE_NEED_FRAME:

            go = 0;

            break;

        case SCHRO_STATE_AGAIN:

            break;

        default:

            av_log(avccontext, AV_LOG_ERROR, "Unknown Schro Encoder state\n");

            return -1;

        }

    }

    /* Copy 'next' frame in queue. */

    if (p_schro_params->enc_frame_queue.size == 1 &&

        p_schro_params->eos_pulled)

        last_frame_in_sequence = 1;

    p_frame_output = ff_dirac_schro_queue_pop(&p_schro_params->enc_frame_queue);

    if (!p_frame_output)

        return 0;

    memcpy(frame, p_frame_output->p_encbuf, p_frame_output->size);

    avccontext->coded_frame->key_frame = p_frame_output->key_frame;

    /* Use the frame number of the encoded frame as the pts. It is OK to

     * do so since Dirac is a constant frame rate codec. It expects input

     * to be of constant frame rate. */

    avccontext->coded_frame->pts = p_frame_output->frame_num;

    enc_size = p_frame_output->size;

    /* Append the end of sequence information to the last frame in the

     * sequence. */

    if (last_frame_in_sequence && p_schro_params->enc_buf_size > 0) {

        memcpy(frame + enc_size, p_schro_params->enc_buf,

               p_schro_params->enc_buf_size);

        enc_size += p_schro_params->enc_buf_size;

        av_freep(&p_schro_params->enc_buf);

        p_schro_params->enc_buf_size = 0;

    }

    /* free frame */

    SchroedingerFreeFrame(p_frame_output);

    return enc_size;

}

static int libschroedinger_encode_close(AVCodecContext *avccontext)

{

    FfmpegSchroEncoderParams* p_schro_params = avccontext->priv_data;

    /* Close the encoder. */

    schro_encoder_free(p_schro_params->encoder);

    /* Free data in the output frame queue. */

    ff_dirac_schro_queue_free(&p_schro_params->enc_frame_queue,

                              SchroedingerFreeFrame);

    /* Free the encoder buffer. */

    if (p_schro_params->enc_buf_size)

        av_freep(&p_schro_params->enc_buf);

    /* Free the video format structure. */

    av_freep(&p_schro_params->format);

    return 0;

}

AVCodec ff_libschroedinger_encoder = {

    "libschroedinger",

    AVMEDIA_TYPE_VIDEO,

    CODEC_ID_DIRAC,

    sizeof(FfmpegSchroEncoderParams),

    libschroedinger_encode_init,

    libschroedinger_encode_frame,

    libschroedinger_encode_close,

   .capabilities = CODEC_CAP_DELAY,

   .pix_fmts     = (const enum PixelFormat[]){PIX_FMT_YUV420P, PIX_FMT_YUV422P, PIX_FMT_YUV444P, PIX_FMT_NONE},

   .long_name    = NULL_IF_CONFIG_SMALL("libschroedinger Dirac 2.2"),

};