- in encx264, if an video frame is larger than init_delay split it into pieces so we don't get jerky output caused by out-of-order frames.

 - add an explicit EOF for all streams, not just video.
 - don't generate extra audio silence at the end of an encode (don't need it with explicit eof).
 - get rid of 80ms initial delay in AAC encode & flush final four frames buffered in encoder.
 - put mp4 'chap' atom on first track (usually video) rather than first audio track since we can now do video without audio (atom just needs to go on an enabled media track & video is always enabled).


git-svn-id: svn://svn.handbrake.fr/HandBrake/trunk@1581 b64f7644-9d1e-0410-96f1-a4d463321fa5

1 files changed, 274 insertions, 191 deletions

diff --git a/libhb/encx264.c b/libhb/encx264.c
index 57a2fe281..caeccb646 100644
--- a/libhb/encx264.c
+++ b/libhb/encx264.c
@@ -30,16 +30,16 @@ hb_work_object_t hb_encx264 =
  * to x264_encoder_encode. Since frames are uniquely identified by their
  * timestamp, we use some bits of the timestamp as an index. The LSB is
  * chosen so that two successive frames will have different values in the
- * bits over any plausible range of frame rates. (Starting with bit 9 allows
- * any frame rate slower than 175fps.) The MSB determines the size of the array.
+ * bits over any plausible range of frame rates. (Starting with bit 8 allows
+ * any frame rate slower than 352fps.) The MSB determines the size of the array.
  * It is chosen so that two frames can't use the same slot during the
  * encoder's max frame delay (set by the standard as 16 frames) and so
  * that, up to some minimum frame rate, frames are guaranteed to map to
- * different slots. (An MSB of 16 which is 2^(16-9+1) = 256 slots guarantees
- * no collisions down to a rate of 1.4 fps).
+ * different slots. (An MSB of 17 which is 2^(17-8+1) = 1024 slots guarantees
+ * no collisions down to a rate of .7 fps).
  */
-#define FRAME_INFO_MAX2 (9)     // 2^9 = 512; 90000/512 = 175 frames/sec
-#define FRAME_INFO_MIN2 (16)    // 2^16 = 65536; 90000/65536 = 1.4 frames/sec
+#define FRAME_INFO_MAX2 (8)     // 2^8 = 256; 90000/256 = 352 frames/sec
+#define FRAME_INFO_MIN2 (17)    // 2^17 = 128K; 90000/131072 = 1.4 frames/sec
 #define FRAME_INFO_SIZE (1 << (FRAME_INFO_MIN2 - FRAME_INFO_MAX2 + 1))
 #define FRAME_INFO_MASK (FRAME_INFO_SIZE - 1)
 
@@ -377,228 +377,311 @@ static int64_t get_frame_duration( hb_work_private_t * pv, int64_t pts )
     return pv->frame_info[i].duration;
 }
 
-int encx264Work( hb_work_object_t * w, hb_buffer_t ** buf_in,
-                  hb_buffer_t ** buf_out )
+static hb_buffer_t *nal_encode( hb_work_object_t *w, x264_picture_t *pic_out,
+                                int i_nal, x264_nal_t *nal )
 {
-    hb_work_private_t * pv = w->private_data;
-    hb_job_t    * job = pv->job;
-    hb_buffer_t * in = *buf_in, * buf;
-    x264_picture_t   pic_out;
-    int           i_nal;
-    x264_nal_t  * nal;
-    int i;
-
-    if( in->data )
+    hb_buffer_t *buf = NULL;
+    hb_work_private_t *pv = w->private_data;
+    hb_job_t *job = pv->job;
+
+    /* Get next DTS value to use */
+    int64_t dts_start = pv->dts_next;
+
+    /* compute the stop time based on the original frame's duration */
+    int64_t dts_stop  = dts_start + get_frame_duration( pv, pic_out->i_pts );
+    pv->dts_next = dts_stop;
+
+    /* Should be way too large */
+    buf = hb_buffer_init( 3 * job->width * job->height / 2 );
+    buf->size = 0;
+    buf->frametype = 0;
+    buf->start = dts_start;
+    buf->stop  = dts_stop;
+
+    /* Store the output presentation time stamp from x264 for use by muxmp4
+       in off-setting b-frames with the CTTS atom. */
+    buf->renderOffset = pic_out->i_pts - dts_start + pv->init_delay;
+    if ( buf->renderOffset < 0 )
     {
-        /*
-         * Point x264 at our current buffers Y(UV) data.
-         */
-        pv->pic_in.img.plane[0] = in->data;
-
-        if( job->grayscale )
-        {
-            /* XXX x264 has currently no option for grayscale encoding */
-            memset( pv->pic_in.img.plane[1], 0x80, job->width * job->height / 4 );
-            memset( pv->pic_in.img.plane[2], 0x80, job->width * job->height / 4 );
-        }
-        else
+        if ( dts_start - pic_out->i_pts > pv->max_delay )
         {
-            /*
-             * Point x264 at our buffers (Y)UV data
-             */
-            pv->pic_in.img.plane[1] = in->data + job->width * job->height;
-            pv->pic_in.img.plane[2] = in->data + 5 * job->width *
-                job->height / 4;
+            pv->max_delay = dts_start - pic_out->i_pts;
+            hb_log( "encx264: init_delay too small: "
+                    "is %lld need %lld", pv->init_delay,
+                    pv->max_delay );
         }
+        buf->renderOffset = 0;
+    }
 
-        if( pv->dts_next == -1 )
+    /* Encode all the NALs we were given into buf.
+       NOTE: This code assumes one video frame per NAL (but there can
+             be other stuff like SPS and/or PPS). If there are multiple
+             frames we only get the duration of the first which will
+             eventually screw up the muxer & decoder. */
+    int i;
+    for( i = 0; i < i_nal; i++ )
+    {
+        int data = buf->alloc - buf->size;
+        int size = x264_nal_encode( buf->data + buf->size, &data, 1, &nal[i] );
+        if( size < 1 )
         {
-            /* we don't have a start time yet so use the first frame's
-             * start. All other frame times will be determined by the
-             * sum of the prior output frame durations in *DTS* order
-             * (not by the order they arrive here). This timing change is
-             * essential for VFR with b-frames but a complete nop otherwise.
-             */
-            pv->dts_next = in->start;
+            continue;
         }
-        if( in->new_chap && job->chapter_markers )
+
+        if( job->mux & HB_MUX_AVI )
         {
-            /* chapters have to start with an IDR frame so request that this
-               frame be coded as IDR. Since there may be up to 16 frames
-               currently buffered in the encoder remember the timestamp so
-               when this frame finally pops out of the encoder we'll mark
-               its buffer as the start of a chapter. */
-            pv->pic_in.i_type = X264_TYPE_IDR;
-            if( pv->next_chap == 0 )
+            if( nal[i].i_ref_idc == NAL_PRIORITY_HIGHEST )
             {
-                pv->next_chap = in->start;
-                pv->chap_mark = in->new_chap;
+                buf->frametype = HB_FRAME_KEY;
             }
-            /* don't let 'work_loop' put a chapter mark on the wrong buffer */
-            in->new_chap = 0;
+            buf->size += size;
+            continue;
         }
-        else
+
+        /* H.264 in .mp4 or .mkv */
+        int naltype = buf->data[buf->size+4] & 0x1f;
+        if ( naltype == 0x7 || naltype == 0x8 )
         {
-            pv->pic_in.i_type = X264_TYPE_AUTO;
+            // Sequence Parameter Set & Program Parameter Set go in the
+            // mp4 header so skip them here
+            continue;
         }
-        pv->pic_in.i_qpplus1 = 0;
 
-        /* XXX this is temporary debugging code to check that the upstream
-         * modules (render & sync) have generated a continuous, self-consistent
-         * frame stream with the current frame's start time equal to the
-         * previous frame's stop time.
-         */
-        if( pv->last_stop != in->start )
+        /* H.264 in mp4 (stolen from mp4creator) */
+        buf->data[buf->size+0] = ( ( size - 4 ) >> 24 ) & 0xFF;
+        buf->data[buf->size+1] = ( ( size - 4 ) >> 16 ) & 0xFF;
+        buf->data[buf->size+2] = ( ( size - 4 ) >>  8 ) & 0xFF;
+        buf->data[buf->size+3] = ( ( size - 4 ) >>  0 ) & 0xFF;
+
+        /* Decide what type of frame we have. */
+        switch( pic_out->i_type )
         {
-            hb_log("encx264 input continuity err: last stop %lld  start %lld",
-                    pv->last_stop, in->start);
+            case X264_TYPE_IDR:
+                buf->frametype = HB_FRAME_IDR;
+                /* if we have a chapter marker pending and this
+                   frame's presentation time stamp is at or after
+                   the marker's time stamp, use this as the
+                   chapter start. */
+                if( pv->next_chap != 0 && pv->next_chap <= pic_out->i_pts )
+                {
+                    pv->next_chap = 0;
+                    buf->new_chap = pv->chap_mark;
+                }
+                break;
+
+            case X264_TYPE_I:
+                buf->frametype = HB_FRAME_I;
+                break;
+
+            case X264_TYPE_P:
+                buf->frametype = HB_FRAME_P;
+                break;
+
+            case X264_TYPE_B:
+                buf->frametype = HB_FRAME_B;
+                break;
+
+        /*  This is for b-pyramid, which has reference b-frames
+            However, it doesn't seem to ever be used... */
+            case X264_TYPE_BREF:
+                buf->frametype = HB_FRAME_BREF;
+                break;
+
+            // If it isn't the above, what type of frame is it??
+            default:
+                buf->frametype = 0;
+                break;
         }
-        pv->last_stop = in->stop;
 
-        // Remember info about this frame that we need to pass across
-        // the x264_encoder_encode call (since it reorders frames).
-        save_frame_info( pv, in );
+        /* Since libx264 doesn't tell us when b-frames are
+           themselves reference frames, figure it out on our own. */
+        if( (buf->frametype == HB_FRAME_B) &&
+            (nal[i].i_ref_idc != NAL_PRIORITY_DISPOSABLE) )
+            buf->frametype = HB_FRAME_BREF;
 
-        /* Feed the input DTS to x264 so it can figure out proper output PTS */
-        pv->pic_in.i_pts = in->start;
+        buf->size += size;
+    }
+    // make sure we found at least one video frame
+    if ( buf->size <= 0 )
+    {
+        // no video: back up the output time stamp then free the buf
+        pv->dts_next = buf->start;
+        hb_buffer_close( &buf );
+    }
+    return buf;
+}
+
+static hb_buffer_t *x264_encode( hb_work_object_t *w, hb_buffer_t *in )
+{
+    hb_work_private_t *pv = w->private_data;
+    hb_job_t *job = pv->job;
 
-        x264_encoder_encode( pv->x264, &nal, &i_nal,
-                             &pv->pic_in, &pic_out );
+    /* Point x264 at our current buffers Y(UV) data.  */
+    pv->pic_in.img.plane[0] = in->data;
+
+    if( job->grayscale )
+    {
+        /* XXX x264 has currently no option for grayscale encoding */
+        memset( pv->pic_in.img.plane[1], 0x80, job->width * job->height / 4 );
+        memset( pv->pic_in.img.plane[2], 0x80, job->width * job->height / 4 );
     }
     else
     {
-        x264_encoder_encode( pv->x264, &nal, &i_nal,
-                             NULL, &pic_out );
-        /* No more delayed B frames */
-        if( i_nal == 0 )
-        {
-            *buf_out = NULL;
-            return HB_WORK_DONE;
-        }
-        else
+        /* Point x264 at our buffers (Y)UV data */
+        pv->pic_in.img.plane[1] = in->data + job->width * job->height;
+        pv->pic_in.img.plane[2] = in->data + 5 * job->width * job->height / 4;
+    }
+
+    if( pv->dts_next == -1 )
+    {
+        /* we don't have a start time yet so use the first frame's
+         * start. All other frame times will be determined by the
+         * sum of the prior output frame durations in *DTS* order
+         * (not by the order they arrive here). This timing change is
+         * essential for VFR with b-frames but a complete nop otherwise.
+         */
+        pv->dts_next = in->start;
+    }
+    if( in->new_chap && job->chapter_markers )
+    {
+        /* chapters have to start with an IDR frame so request that this
+           frame be coded as IDR. Since there may be up to 16 frames
+           currently buffered in the encoder remember the timestamp so
+           when this frame finally pops out of the encoder we'll mark
+           its buffer as the start of a chapter. */
+        pv->pic_in.i_type = X264_TYPE_IDR;
+        if( pv->next_chap == 0 )
         {
-        /*  Since we output at least one more frame, drop another empty
-            one onto our input fifo.  We'll keep doing this automatically
-            until we stop getting frames out of the encoder. */
-            hb_fifo_push(w->fifo_in, hb_buffer_init(0));
+            pv->next_chap = in->start;
+            pv->chap_mark = in->new_chap;
         }
+        /* don't let 'work_loop' put a chapter mark on the wrong buffer */
+        in->new_chap = 0;
     }
-
-    if( i_nal )
+    else
     {
-        /* Should be way too large */
-        buf        = hb_buffer_init( 3 * job->width * job->height / 2 );
-        buf->size  = 0;
-        buf->frametype   = 0;
+        pv->pic_in.i_type = X264_TYPE_AUTO;
+    }
+    pv->pic_in.i_qpplus1 = 0;
 
-        /* Get next DTS value to use */
-        int64_t dts_start = pv->dts_next;
+    /* XXX this is temporary debugging code to check that the upstream
+     * modules (render & sync) have generated a continuous, self-consistent
+     * frame stream with the current frame's start time equal to the
+     * previous frame's stop time.
+     */
+    if( pv->last_stop != in->start )
+    {
+        hb_log("encx264 input continuity err: last stop %lld  start %lld",
+                pv->last_stop, in->start);
+    }
+    pv->last_stop = in->stop;
 
-        /* compute the stop time based on the original frame's duration */
-        int64_t dts_stop  = dts_start + get_frame_duration( pv, pic_out.i_pts );
-        pv->dts_next = dts_stop;
+    // Remember info about this frame that we need to pass across
+    // the x264_encoder_encode call (since it reorders frames).
+    save_frame_info( pv, in );
 
-        for( i = 0; i < i_nal; i++ )
-        {
-            int size, data;
+    /* Feed the input DTS to x264 so it can figure out proper output PTS */
+    pv->pic_in.i_pts = in->start;
 
-            data = buf->alloc - buf->size;
-            if( ( size = x264_nal_encode( buf->data + buf->size, &data,
-                                          1, &nal[i] ) ) < 1 )
-            {
-                continue;
-            }
+    x264_picture_t pic_out;
+    int i_nal;
+    x264_nal_t *nal;
 
-            if( job->mux & HB_MUX_AVI )
-            {
-                if( nal[i].i_ref_idc == NAL_PRIORITY_HIGHEST )
-                {
-                    buf->frametype = HB_FRAME_KEY;
-                }
-                buf->size += size;
-                continue;
-            }
+    x264_encoder_encode( pv->x264, &nal, &i_nal, &pv->pic_in, &pic_out );
+    if ( i_nal > 0 )
+    {
+        return nal_encode( w, &pic_out, i_nal, nal );
+    }
+    return NULL;
+}
 
-            /* H.264 in .mp4 */
-            switch( buf->data[buf->size+4] & 0x1f )
-            {
-                case 0x7:
-                case 0x8:
-                    /* SPS, PPS */
-                    break;
-
-                default:
-                    /* H.264 in mp4 (stolen from mp4creator) */
-                    buf->data[buf->size+0] = ( ( size - 4 ) >> 24 ) & 0xFF;
-                    buf->data[buf->size+1] = ( ( size - 4 ) >> 16 ) & 0xFF;
-                    buf->data[buf->size+2] = ( ( size - 4 ) >>  8 ) & 0xFF;
-                    buf->data[buf->size+3] = ( ( size - 4 ) >>  0 ) & 0xFF;
-                    switch( pic_out.i_type )
-                    {
-                    /*  Decide what type of frame we have. */
-                        case X264_TYPE_IDR:
-                            buf->frametype = HB_FRAME_IDR;
-                            /* if we have a chapter marker pending and this
-                               frame's presentation time stamp is at or after
-                               the marker's time stamp, use this as the
-                               chapter start. */
-                            if( pv->next_chap != 0 && pv->next_chap <= pic_out.i_pts )
-                            {
-                                pv->next_chap = 0;
-                                buf->new_chap = pv->chap_mark;
-                            }
-                            break;
-                        case X264_TYPE_I:
-                            buf->frametype = HB_FRAME_I;
-                            break;
-                        case X264_TYPE_P:
-                            buf->frametype = HB_FRAME_P;
-                            break;
-                        case X264_TYPE_B:
-                            buf->frametype = HB_FRAME_B;
-                            break;
-                    /*  This is for b-pyramid, which has reference b-frames
-                        However, it doesn't seem to ever be used... */
-                        case X264_TYPE_BREF:
-                            buf->frametype = HB_FRAME_BREF;
-                            break;
-                    /*  If it isn't the above, what type of frame is it?? */
-                        default:
-                            buf->frametype = 0;
-                    }
+int encx264Work( hb_work_object_t * w, hb_buffer_t ** buf_in,
+                  hb_buffer_t ** buf_out )
+{
+    hb_work_private_t *pv = w->private_data;
+    hb_buffer_t *in = *buf_in;
 
-                    /* Since libx264 doesn't tell us when b-frames are
-                       themselves reference frames, figure it out on our own. */
-                    if( (buf->frametype == HB_FRAME_B) && (nal[i].i_ref_idc != NAL_PRIORITY_DISPOSABLE) )
-                        buf->frametype = HB_FRAME_BREF;
+    if( in->size <= 0 )
+    {
+        // EOF on input. Flush any frames still in the decoder then
+        // send the eof downstream to tell the muxer we're done.
+        x264_picture_t pic_out;
+        int i_nal;
+        x264_nal_t *nal;
+        hb_buffer_t *last_buf = NULL;
+
+        while (1)
+        {
+            x264_encoder_encode( pv->x264, &nal, &i_nal, NULL, &pic_out );
+            if ( i_nal <= 0 )
+                break;
 
-                    /* Store the output presentation time stamp
-                       from x264 for use by muxmp4 in off-setting
-                       b-frames with the CTTS atom. */
-                    buf->renderOffset = pic_out.i_pts - dts_start + pv->init_delay;
-                    if ( buf->renderOffset < 0 )
-                    {
-                        if ( dts_start - pic_out.i_pts > pv->max_delay )
-                        {
-                            pv->max_delay = dts_start - pic_out.i_pts;
-                            hb_log( "encx264: init_delay too small: "
-                                    "is %lld need %lld", pv->init_delay,
-                                    pv->max_delay );
-                        }
-                        buf->renderOffset = 0;
-                    }
-                    buf->size += size;
-            }
+            hb_buffer_t *buf = nal_encode( w, &pic_out, i_nal, nal );
+            if ( last_buf == NULL )
+                *buf_out = buf;
+            else
+                last_buf->next = buf;
+            last_buf = buf;
         }
-        /* Send out the next dts values */
-        buf->start = dts_start;
-        buf->stop  = dts_stop;
+        // Flushed everything - add the eof to the end of the chain.
+        if ( last_buf == NULL )
+            *buf_out = in;
+        else
+            last_buf->next = in;
+
+        *buf_in = NULL;
+        return HB_WORK_DONE;
     }
 
+    // Not EOF - encode the packet & wrap it in a NAL
+    if ( pv->init_delay && in->stop - in->start > pv->init_delay )
+    {
+        // This frame's duration is larger than the time allotted for b-frame
+        // reordering. That means that if it's used as a reference the decoder
+        // won't be able to move it early enough to render it in correct
+        // sequence & the playback will have odd jumps & twitches. To make
+        // sure this doesn't happen we pretend this frame is multiple
+        // frames, each with duration <= init_delay. Since each of these
+        // new frames contains the same image the visual effect is identical
+        // to the original but the resulting stream can now be coded without
+        // error. We take advantage of the fact that x264 buffers frame
+        // data internally to feed the same image into the encoder multiple
+        // times, just changing its start & stop times each time.
+        int64_t orig_stop = in->stop;
+        int64_t new_stop = in->start;
+        hb_buffer_t *last_buf = NULL;
+
+        // We want to spread the new frames uniformly over the total time
+        // so that we don't end up with a very short frame at the end.
+        // In the number of pieces calculation we add in init_delay-1 to
+        // round up but not add an extra piece if the frame duration is
+        // a multiple of init_delay. The final increment of frame_dur is
+        // to restore the bits that got truncated by the divide on the
+        // previous line. If we don't do this we end up with an extra tiny
+        // frame at the end whose duration is npieces-1.
+        int64_t frame_dur = orig_stop - new_stop;
+        int64_t npieces = ( frame_dur + pv->init_delay - 1 ) / pv->init_delay;
+        frame_dur /= npieces;
+        ++frame_dur;
+
+        while ( in->start < orig_stop )
+        {
+            new_stop += frame_dur;
+            if ( new_stop > orig_stop )
+                new_stop = orig_stop;
+            in->stop = new_stop;
+            hb_buffer_t *buf = x264_encode( w, in );
+            if ( last_buf == NULL )
+                *buf_out = buf;
+            else
+                last_buf->next = buf;
+            last_buf = buf;
+            in->start = new_stop;
+        }
+    }
     else
-        buf = NULL;
-
-    *buf_out = buf;
-
+    {
+        *buf_out = x264_encode( w, in );
+    }
     return HB_WORK_OK;
 }